You are given two reports by the government agency.  

Report 1:
Names for Navy ships traditionally have been chosen and announced by the Secretary of the Navy, under the direction of the President and in accordance with rules prescribed by Congress. For most of the 19 th century, U.S. law included language explicitly assigning the Secretary of the Navy the task of naming new Navy ships. The reference to the Secretary of the Navy disappeared from the U.S. Code in 1925. The code today (10 U.S.C. §8662) is silent on the issue of who has the authority to name new Navy ships, but the Secretary of the Navy arguably retains implicit authority, given the location of Section 8662 in subtitle C of Title 10, which covers the Navy and Marine Corps. In discussing its name-selection process, the Naval History and Heritage Command—the Navy's in-house office of professional historians—cites the above-mentioned laws and states the following: As with many other things, the procedures and practices involved in Navy ship naming are as much, if not more, products of evolution and tradition than of legislation. As we have seen, the names for new ships are personally decided by the Secretary of the Navy. The Secretary can rely on many sources to help him reach his decisions. Each year, the Navy History and Heritage Command (NHHC) compiles primary and alternate ship name recommendations and forwards these to the Chief of Naval Operations by way of the chain of command. These recommendations are the result of research into the history of the Navy and by suggestions submitted by service members, Navy veterans, and the public. Ship name source records at NHHC reflect the wide variety of name sources that have been used in the past, particularly since World War I. Ship name recommendations are conditioned by such factors as the name categories for ship types now being built, as approved by the Secretary of the Navy; the distribution of geographic names of ships of the fleet; names borne by previous ships that distinguished themselves in service; names recommended by individuals and groups; and names of naval leaders, national figures, and deceased members of the Navy and Marine Corps who have been honored for heroism in war or for extraordinary achievement in peace. In its final form, after consideration at the various levels of command, the Chief of Naval Operations signs the memorandum recommending names for the current year's building program and sends it to the Secretary of the Navy. The Secretary considers these nominations, along with others he receives, as well as his own thoughts in this matter. At appropriate times, he selects names for specific ships and announces them. While there is no set time for assigning a name, it is customarily done before the ship is christened. The ship's sponsor─the person who will christen the ship─is also selected and invited by the Secretary. In the case of ships named for individuals, an effort is made to identify the eldest living direct female descendant of that individual to perform the role of ship's sponsor. For ships with other name sources, it is customary to honor the wives of senior naval officers or public officials. A July 2012 Navy report to Congress on the Navy's policies and practices for naming ships (see next section) states the following: Once a type/class naming convention [i.e., a general rule or guideline for how ships of a certain type or class are to be named] is established, Secretaries can rely on many sources to help in the final selection of a ship name. For example, sitting Secretaries can solicit ideas and recommendations from either the Chief of Naval Operations (CNO) or the Commandant of the Marine Corps (CMC), or both. They can also task the Naval Heritage and History Command to compile primary and alternate ship name recommendations that are the result of research into the history of the Navy's battle force or particular ship names. Secretaries also routinely receive formal suggestions for ship names from concerned citizens, active and retired service members, or members of Congress. Finally, Congress can enact provisions in Public Law that express the sense of the entire body about new ship naming conventions or specific ship names. Regardless of the origin of the recommendations, however, the final selection of a ship's name is the Secretary's to make, informed and guided by his own thoughts, counsel, and preferences. At the appropriate time—normally sometime after the ship has been either authorized or appropriated by Congress and before its keel laying or christening—the Secretary records his decision with a formal naming announcement. On July 13, 2012, the Navy submitted to Congress a 73-page report on the Navy's policies and practices for naming ships. The report was submitted in response to Section 1014 of the FY2012 National Defense Authorization Act ( H.R. 1540 / P.L. 112-81 of December 31, 2011). The executive summary of the Navy's report is reprinted here as Appendix A . Rules for giving certain types of names to certain types of Navy ships have evolved over time. Attack submarines, for example, were once named for fish, then later for cities, and most recently for states, while cruisers were once named for cities, then later for states, and most recently for battles. State names, to cite another example, were given to battleships, then later to nuclear-powered cruisers and ballistic missile submarines, and are now being given to attack submarines. The Naval History and Heritage Command states the following: "How will the Navy name its ships in the future? It seems safe to say that the evolutionary process of the past will continue; as the fleet itself changes, so will the names given to its ships. It seems equally safe, however, to say that future decisions in this area will continue to demonstrate regard for the rich history and valued traditions of the United States Navy." The July 2012 Navy report to Congress states that "US Navy ship-naming policies, practices, and 'traditions' are not fixed; they evolve constantly over time." The report also states that "Just as [ship] type naming conventions change over time to accommodate technological change as well as choices made by Secretaries, they also change over time as every Secretary makes their own interpretation of the original naming convention." There have been numerous exceptions to the Navy's ship-naming rules, particularly for the purpose of naming a ship for a person when the rule for that type of ship would have called for it to be named for something else. The July 2012 report to Congress cites exceptions to ship naming rules dating back to the earliest days of the republic, and states that "a Secretary's discretion to make exceptions to ship-naming conventions is one of the Navy's oldest ship-naming traditions." The report argues that exceptions made for the purpose of naming ships for Presidents or Members of Congress have occurred frequently enough that, rather than being exceptions, they constitute a "special cross-type naming convention" for Presidents and Members of Congress. This CRS report continues to note, as exceptions to basic class naming rules, instances where ships other than aircraft carriers have been named for Presidents or Members of Congress. Some observers have perceived a breakdown in, or corruption of, the rules for naming Navy ships. Such observers might cite, for example, the three-ship Seawolf (SSN-21) class of attack submarines— Seawolf (SSN-21), Connecticut (SSN-22), and Jimmy Carter (SSN-23)—which were named for a fish, a state, and a President, respectively, reflecting no apparent class naming rule. The July 2012 Navy report to Congress states the following: "Current ship naming policies and practices fall well within the historic spectrum of policies and practices for naming vessels of the Navy, and are altogether consistent with ship naming customs and traditions." For ship types now being procured for the Navy, or recently procured for the Navy, naming rules (and exceptions thereto) are summarized below. The July 2012 Navy report to Congress discusses current naming rules (and exceptions thereto) at length. On December 14, 2016, the Navy named the first of its 12 planned next-generation ballistic missile submarines Columbia (SSBN-826), in honor of the District of Columbia. The 12 planned boats are consequently now referred to as Columbia -class or SSBN-826 class boats. The Navy has not stated what the naming rule for these ships will be. Given the selection of Columbia as the name of the lead ship, possibilities for the naming rule include (but are not necessarily limited to) cities, capital cities, or states and federal districts and territories. It is also possible that the name Columbia will turn out to be an exception to the naming rule for the class. The current USS Columbia (SSN-771)—a Los Angeles (SSN-688) class attack submarine that was named for Columbia, SC; Columbia, IL; and Columbia, MO —entered service in 1995 and will reach the end of its 33-year expected service life in 2028, at about the time that construction of SSBN-826 is scheduled to be completed. If the service life of SSN-771 is extended for several years, it would remain in service after the commissioning of SSBN-826. This would create an issue to be resolved, since 10 U.S.C. §8662(a) states, "Not more than one vessel of the Navy may have the same name." One possible step for resolving such an issue would be to change the name of SSBN-826 to something else, such as District of Columbia —a step that could be viewed as somewhat similar to the below-discussed instance in which the name of the Los Angles-class submarine SSN-705 was changed from Corpus Christi to City of Corpus Christi (see " Congressional Responses to Announced Navy Ship-Naming Decisions " below). Virginia (SSN-774) class attack submarines are being named for states. An exception occurred on January 8, 2009, when then-Secretary of the Navy Donald Winter announced that SSN-785 would be named for former Senator John Warner. Another exception occurred on January 9, 2014, when then-Secretary of the Navy Ray Mabus announced that SSN-795, the second of the two Virginia-class boats procured in FY2015, would be named for Admiral Hyman G. Rickover, who served for many years as director of the Navy's nuclear propulsion program. As of May 6, 2019, the Navy has announced names for all Virginia-class boats through SSN-801, the second of two Virginia-class boats procured in FY2018. A total of 30 Virginia-class boats have been procured through FY2019, of which 26 have been named for states. (Two were named for people and the two procured in FY2019 have not yet been named.) The Navy's shipbuilding plan calls for procuring three additional Virginia-class boats in FY2020 and two per year FY2021 and subsequent years. The 26 state-named Virginia-class boats procured through FY2018, together with the additional Virginia-class boats planned for procurement in FY2020 and subsequent years and the 17 existing state-named Ohio (SSBN-726) class SSBNs and cruise missile submarine (SSGNs), could make for a total of more than 50 boats starting around FY2022. Thus, starting around FY2022, the Navy might run out of state names for Virginia-class boats, and consequently might need to either amend the Virginia-class naming rule or begin making a series of exceptions to the rule. The July 2012 Navy report to Congress states that "while carrier names are still 'individually considered,' they are now generally named in honor of past US Presidents." Of the 14 most recently named aircraft carriers (those with hull numbers 67 through 80), 10 have been named for U.S. Presidents and 2 for Members of Congress. The Navy is currently procuring Gerald R. Ford (CVN-78) class carriers. On January 16, 2007, the Navy announced that CVN-78, the lead ship in the CVN-78 class, would be named for President Gerald R. Ford. On May 29, 2011, the Navy announced that CVN-79, the second ship in the class, would be named for President John F. Kennedy. On December 1, 2012, the Navy announced that CVN-80, the third ship in the class, would be named Enterprise . The Navy made the announcement on the same day that it deactivated the 51-year-old aircraft carrier CVN-65, also named Enterprise . CVN-80 is the ninth Navy ship named Enterprise . CVN-80 was procured in the FY2018 budget, which Congress considered in 2017. If CVN-80, like most Navy ships, had been named at about the time of procurement, or later, rather than in 2012, it would have been named by the current Secretary of the Navy, Richard Spencer. The July 2012 Navy report to Congress, which was produced when Ray Mabus was the Secretary of the Navy, states that Secretary [of the Navy Ray] Mabus values the ability to consider [aircraft] carrier names on an individual, case‐by‐case basis, for two reasons. First, it will allow a future Secretary to name a future fleet aircraft carrier for someone or something other than a former President. Indeed, Secretary Mabus has a particular name in mind. With the scheduled decommissioning of USS Enterprise (CVN 65), perhaps the most famous ship name in US Navy history besides USS Constitution will be removed from the Naval Vessel Register. Secretary Mabus believes this circumstance could be remedied by bestowing the Enterprise's storied name on a future carrier. Prior to the naming of CVN-80, the most recent carrier that was not named for a President or Member of Congress was the second of the 14 most recently named carriers, Nimitz (CVN-68), which was procured in FY1967. Destroyers traditionally have been named for famous U.S. naval leaders and distinguished heroes. The July 2012 Navy report to Congress discusses this tradition and states more specifically that destroyers are being named for deceased members of the Navy, Marine Corps, and Coast Guard, including Secretaries of the Navy. Exceptions since 2012 (all of which involve Arleigh Burke [DDG-51] class destroyers) include the following: On May 7, 2012, the Navy announced that it was naming DDG-116 for a living person, Thomas Hudner. On May 23, 2013, the Navy announced that it was naming DDG-117 for a living person, Paul Ignatius, and that it was naming DDG-118 for the late Senator Daniel Inouye, who served in the U.S. Army during World War II. On March 31 and April 5, 2016, it was reported that the Navy was naming DDG-120 for a living person, former Senator Carl Levin. On July 28, 2016, the Navy announced that it was naming DDG-124 for a living person, Harvey C. Barnum Jr. On July 11, 2018, Secretary of the Navy Richard Spencer announced that the Navy was expanding the name of the destroyer John. S. McCain (DDG-56) to include a living person, Senator John S. McCain III (for additional discussion, see the next section below). On May 6, 2019, the Navy announced that it was naming DDG-133 for a living person, former Senator Sam Nunn, who had served in the Coast Guard from 1959 to 1960, and in the Coast Guard Reserve from 1960 until 1968 (for additional discussion, see the section following the next section). As of May 6, 2019, the Navy had announced names for all DDG-51 class destroyers procured through DDG-131, the second of three DDG-51s procured in FY2019, and DDG-133, one of three DDG-51s requested for procurement in FY2020. On July 11, 2018, Secretary of the Navy Richard Spencer announced that the Navy was expanding the name of the destroyer John. S. McCain (DDG-56), originally named for Admiral John S. "Slew" McCain (1884-1945) and his son, Admiral John S. "Jack" McCain, Jr. (1911-1981), to also include Senator John S. McCain III, the grandson of Admiral John S. McCain and the son of Admiral John S. McCain, Jr. DDG-56 was procured in FY1989 and was commissioned into service on July 2, 1994. John S. McCain III served as a Member of the House of Representatives from 1983 to 1987, and as a Senator from 1987 to 2018. Among his committee chairmanships, he was the chairman of the Senate Armed Services Committee from January 3, 2015, until his death on August 25, 2018. He was the Republican Party candidate for President in 2008. On May 6, 2019, the Navy announced that it was naming DDG-133 for former Senator Sam Nunn. Nunn served in the Coast Guard from 1959 to 1960, and in the Coast Guard Reserve from 1960 until 1968. He was a Senator from 1972 to 1997. During his time in the Senate, he was, among other things, the Chairman of the Senate Armed Services Committee from January 1987 to January 1995. The Navy in 2017 initiated a new program, called the FFG(X) program, to build a class of 20 guided-missile frigates (FFGs). The Navy wants to procure the first FFG(X) in FY2020, the second in FY2021, and the remaining 18 at a rate of two per year in FY2022-FY2030. As of May 6, 2019, the Navy had not announced a naming rule for this planned new class of ships. Previous classes of U.S. Navy frigates, like Navy destroyers, were generally named for naval leaders and heroes. Littoral Combat Ships (LCSs) were at first named for U.S. mid-tier cities, small towns, and other U.S. communities. The naming rule was later adjusted to regionally important U.S. cities and communities. An exception occurred on February 10, 2012, when the Navy announced that it was naming LCS-10 for former Representative Gabrielle Giffords. Another exception occurred on February 23, 2018, when President Trump, in a press conference with Australian Prime Minister Malcolm Turnbull, announced that an LCS would be named Canberra , in honor of HMAS Canberra (D33), an Australian cruiser named for the capital city of Australia that fought alongside U.S. Navy forces World War II and was scuttled after being damaged by Japanese attack in the Battle of Savo Island on August 9, 1942. The Navy has identified the LCS to be named Canberra as LCS-30. A previous U.S. Navy ship, the gun cruiser Canberra (CA-70), which served from 1943 to 1947 and again from 1956 to 1970, was similarly named in honor of HMAS Canberra . There is also a current HMAS Canberra (L02), an amphibious assault ship (i.e., helicopter carrier) that entered service in 2014 and now serves as the flagship of the Australian navy. The situation of LCS-30 and L02 sharing the same name will presumably not violate 10 U.S.C. §8662(a)—which states that "not more than one vessel of the Navy may have the same name"—because 10 U.S.C. §8662 is a statute governing the naming of U.S. Navy ships and L02 is not a U.S. Navy ship. As of May 6, 2019, the Navy had posted or announced names for all LCSs up through LCS-30, plus LCS-32, LCS-34, LCS-36, and LCS-38. The Navy also announced on October 9, 2018, that one additional LCS would be named for Cleveland, OH, but the Navy did not specify which LCS would receive this name. A total of 35 LCSs have been procured through FY2019. In addition to LCSs 1-30, 32, 34, 36, and 38, the Navy has identified the 35 th LCS as LCS-31. As of May 6, 2019, this ship was listed by the Navy as having no name. The Navy does not want to procure any more LCSs beyond the 35 that have been procured. If no additional LCSs are procured beyond the 35 that have been procured, LCS-31 will be the last LCS to be named. Given the Navy's October 9, 2018, announcement that one additional LCS would be named for Cleveland, OH, it is possible the Navy will name LCS-31 for Cleveland. Amphibious assault ships (LHAs), which look like medium-sized aircraft carriers, are being named for important battles in which U.S. Marines played a prominent part, and for famous earlier U.S. Navy ships that were not named for battles. The Navy announced on June 27, 2008, that the first LHA-6 class amphibious assault ship, LHA-6, would be named America , a name previously used for an aircraft carrier (CV-66) that served in the Navy from 1965 to 1996. The Navy announced on May 4, 2012, that LHA-7, the second ship in the class, LHA-7, would be named Tripoli , the location of famous Marine battles in the First Barbary War. The Navy reaffirmed this name selection with a more formal announcement on May 30, 2014. On November 9, 2016, the Navy announced that the third ship in the class, LHA-8, will be named Bougainville , the location of a famous World War II campaign in the Pacific. San Antonio (LPD-17) class amphibious ships are being named for major U.S. cities and communities (with major being defined as being one of the top three population centers in a state), and cities and communities attacked on September 11, 2001. An exception occurred on April 23, 2010, when the Navy announced that it was naming LPD-26, the 10 th ship in the class, for the late Representative John P. Murtha. Another exception occurred on May 2, 2018, when the Navy announced that it was naming LPD-29, the 13 th ship in the class, for Navy Captain Richard M. McCool, Jr., who received the Medal of Honor for his actions in World War II and later served in the Korean and Vietnam wars. As of May 6, 2019, the Navy had not announced a name for LPD-30, which was funded in FY2018, and which is to be the first of a new version, or flight, of the LPD-17 class design called the LPD-17 Flight II design. On January 6, 2016, then-Secretary of the Navy Ray Mabus announced that the Navy's new oilers will be named for "people who fought for civil rights and human rights," and that the first ship in the class, TAO-205, which was procured in FY2016, will be named for Representative John Lewis. The ships in this class consequently are now referred to as John Lewis (TAO-205) class ships. The Navy wants to procure a total of 20 John Lewis-class ships. On July 28, 2016, it was reported that the Navy would name the second through sixth ships in the class (i.e., TAOs 206 through 210) for Harvey Milk, Earl Warren, Robert F. Kennedy, Lucy Stone, and Sojourner Truth, respectively. All these names were later posted by the Navy for these ships. The Navy's 14 Lewis and Clark (TAKE-1) class cargo and ammunition ships were named for famous American explorers, trailblazers, and pioneers. The Navy announced on October 9, 2009, that the 13 th ship in the class was being named for the civil rights activist Medgar Evers. The Navy announced on May 18, 2011, that the 14 th ship in the class would be named for civil rights activist Cesar Chavez. Expeditionary Fast Transports (EPFs), which until May 2011 were being procured by the Army as well as by the Navy, were at first named for American traits and values. In December 2009, the naming rule for EPFs was changed to small U.S. cities. At some point between December 2010 and October 2011, it was adjusted to small U.S. cities and counties. As of May 6, 2019, the Navy had posted names for all EPFs through EPF-12, which was procured in FY2016. A 13 th EPF was funded by Congress in FY2018, and a 14 th was funded by Congress in FY2019. The Navy's two Expeditionary Transport Docks (ESDs 1 and 2) and its Expeditionary Sea Bases (ESB 3 and higher) are being named for famous names or places of historical significance to U.S. Marines. Two of these ships have been named for living persons—ESD-2, which was named John Glenn , and ESB-4, which was named for Hershel "Woody" Williams. On November 4, 2017, Secretary of the Navy Richard Spencer announced that the third ESB (ESB-5), which was procured in FY2016, would be named for Marine Corps Vietnam veteran and Medal of Honor recipient Lance Corporal Miguel Keith. This was Spencer's first announced naming of a Navy ship. A fourth ESB (ESB-6) was procured in FY2018, and a fifth (ESB-7) was procured in FY2019. Navy plans calls for procuring a total of six ESBs. On March 12, 2019, the Navy announced that that TATS-6, the first ship in a new class of towing, salvage, and rescue ships (TATSs), would be named Navajo, "in honor of the major contributions that the Navajo people have made to the armed forces," and that ships in this class will be named for prominent Native Americans or Native American tribes. It has been a long time since ships named for certain states were last in commissioned service with the Navy as combat assets. While there is no rule requiring the Navy, in selecting state names for ships, to choose states for which the most time has passed since a ship named for the state has been in commissioned service with the Navy as a combat asset, advocates of naming a ship for a certain state may choose to point out, among other things, the length of time that has transpired since a ship named for the state has been in commissioned service with the Navy as a combat asset. In its announcement of April 13, 2012, that the Navy was naming the Virginia class attack submarines SSNs 786 through 790 for Illinois, Washington, Colorado, Indiana, and South Dakota, respectively, the Department of Defense stated, "None of the five states has had a ship named for it for more than 49 years. The most recent to serve was the battleship Indiana, which was decommissioned in October 1963." The July 2012 Navy report to Congress states the following: "Before deciding on which names to select [for the five submarines], [then-]Secretary [of the Navy Ray] Mabus asked for a list of State names that had been absent the longest from the US Naval Register...." In its announcement of November 19, 2012, that the Navy was naming the Virginia class attack submarine SSN-791 for Delaware, the Department of Defense quoted then-Secretary Mabus as saying, "It has been too long since there has been a USS Delaware in the fleet...." A Navy News Service article about the Navy's September 18, 2014, announcement that the Virginia class attack submarine SSN-792 was being named for Vermont stated that "This is the first ship named for Vermont since 1920[,] when the second USS Vermont was decommissioned." A Navy News Service article about the Navy's October 10, 2014, announcement that the Virginia class attack submarine SSN-793 was being named for Oregon stated that the previous USS Oregon "was a battleship best known for its roles in the Spanish American War when it helped destroy Admiral Cervera's fleet and in the Philippine-American War; it performed blockade duty in Manila Bay and off Lingayen Gulf, served as a station ship, and aided in the capture of Vigan." A Navy News Service article about the Navy's January 19, 2016, announcement that the Virginia-class attack submarine SSN-801 was being named for Utah stated, "The future USS Utah will be the second naval vessel to bear the name; the first, a battleship designated BB-31, was commissioned in 1911 and had a long, honorable time in service.... While conducting anti-gunnery exercises in Pearl Harbor, BB-31 was struck by a torpedo and capsized during the initial stages of the Japanese attack [on December 7, 1941]. She was struck from the Navy record Nov. 13, 1944 and received a battle star for her service in World War I." The Navy's naming announcements for Virginia-class submarines have reduced the group of states for which several decades had passed since a ship named for the state had been in commissioned service with the Navy as a combat asset, and for which no ship by that name is currently under construction. This group used to include Illinois, Delaware, Vermont, Oregon, and Montana, but Virginia-class attack submarines have now been named for these states. (See the Virginia-class attack submarine naming announcements of April 13, 2012; November 19, 2012; September 18, 2014; October 10, 2014; and September 2, 2015, respectively.) As shown in Table 1 , the three states for which the most time now appears to have passed since a ship named for the state has been in commissioned service with the Navy as a combat asset, and for which no ship by that name is currently under construction, are Kansas, Arizona, and Oklahoma. As of May 6, 2019, it has been more than 97 years since the decommissioning on December 16, 1921, of the battleship Kansas (BB-21), the most recent ship named for the state of Kansas that was in commissioned service with the Navy as a combat asset. As discussed earlier in the section on rules for naming SSNs, starting around FY2022, the Navy might run out of state names for Virginia-class boats, and consequently might need to either amend the Virginia-class naming rule or begin making a series of exceptions to the rule. The Navy historically has only rarely named ships for living persons, meaning (throughout this CRS report) persons who were living at the time the name was announced. The Navy stated in February 2012 that The Navy named several ships for living people (ex. George Washington, Ben Franklin, etc.) in the early years of our Republic. The Naval History and Heritage Command (NHHC) believes that the last ship to be named by the Navy in honor of a living person prior to [the aircraft carrier] CARL VINSON (CVN-70) was the brig JEFFERSON (launched in April 1814). Between 1814 and November 18, 1973, when President Nixon announced the naming of CARL VINSON, NHHC does not believe that any ships had been named for a living person by the Navy as NHHC does not have records that would indicate such. The July 2012 Navy report to Congress, noting a case from 1900 that was not included in the above passage, states that the practice of naming ships in honor of deserving Americans or naval leaders while they are still alive can be traced all the way back to the Revolutionary War. At the time, with little established history or tradition, the young Continental Navy looked to honor those who were fighting so hard to earn America's freedom. Consequently, George Washington had no less than five ships named for him before his death; John Adams and James Madison, three apiece; John Hancock, two; and Benjamin Franklin, one. The practice of naming ships after living persons was relatively commonplace up through 1814, when a US Navy brig was named in honor of Thomas Jefferson. However, after the War of 1812, with the US Navy older and more established, and with the list of famous Americans and notable naval heroes growing ever longer, the practice of naming ships after living persons fell into disuse. Indeed, the only exception over the next 150 years came in 1900, when the Navy purchased its first submarine from its still living inventor, John Philip Holland, and Secretary of the Navy John D. Long named her USS Holland (SS 1) in his honor.... [In the early 1970s], however, Department of the Navy leaders were considering the name for CVN 70. Secretary of the Navy John Warner knew the 93 rd Congress had introduced no less than three bills or amendments (none enacted) urging that CVN 70 be named for in honor of Carl Vinson, who served in the House for 50 years and was known as the "Father of the Two-Ocean Navy." Although Secretary Warner felt Congressman Vinson was more than worthy of a ship name, the former Congressman was still alive. Naming a ship for this giant of naval affairs would therefore violate a 160-year old tradition. After considering the pros and cons of doing so, Secretary Warner asked President Richard Nixon's approval to name CVN 70 for the 90-year old statesman. President Nixon readily agreed. Indeed, he personally announced the decision on January 18, 1974.... In hindsight, rather than this decision being a rare exception, it signaled a return to the Continental Navy tradition of occasionally honoring famous living persons with a ship name. Since then, and before the appointment of current Secretary [now then-Secretary] of the Navy Ray Mabus, Secretaries of the Navy have occasionally chosen to follow this new, "old tradition," naming ships in honor of still living former Presidents Jimmy Carter, Ronald Reagan, George H.W. Bush, and Gerald R. Ford; Secretary of the Navy Paul Nitze; Navy Admirals Hyman G. Rickover, Arleigh Burke, and Wayne E. Meyer; Senators John C. Stennis and John Warner; and famous entertainer Bob Hope. Moreover, it is important to note that three of these well-known Americans—Gerald R. Ford, John C. Stennis, and Bob Hope—were so honored after Congress enacted provisions in Public Laws urging the Navy to do so. By its own actions, then, Congress has acknowledged the practice of occasionally naming ships for living persons, if not outright approved of it. In other words, while naming ships after living persons remains a relatively rare occurrence—about three per decade since 1970—it is now an accepted but sparingly used practice for Pragmatic Secretaries [of the Navy] of both parties. For them, occasionally honoring an especially deserving member of Congress, US naval leader, or famous American with a ship name so that they might end their days on earth knowing that their life's work is both recognized and honored by America's Navy-Marine Corps Team, and that their spirit will accompany and inspire the Team in battle, is sometimes exactly the right thing to do. As shown in Table 2 , since the naming of CVN-70 for Carl Vinson in 1974, at least 21 U.S. military ships have been named for persons who were living at the time the name was announced. Eight of the 21 were announced between January 2012 and March 2016, including three announced in 2012 and four announced in 2016. In four of the six most-recent instances, the ships were named for current or former Members of Congress. The most recent instance occurred on May 6, 2019, when the Navy announced that it was naming the destroyer DDG-51 for former Senator Sam Nunn. (For further discussion of that naming action, see the earlier section on names for destroyers.) A June 15, 2017, blog post states the following: Four [past U.S. Navy] ships have been named for Confederate officers: the [ballistic missile submarine/attack submarine] USS Robert E. Lee (SSBN-601[/SSN-601]) [commissioned 1960; decommissioned 1983], the [ballistic missile submarine] USS Stonewall Jackson (SSBN-634) [commissioned 1964; decommissioned 1995], the [submarine tender] USS Hunley (AS-31) [commissioned 1962; decommissioned 1994], and the [submarine tender] USS Dixon (AS-37) [commissioned 1971; decommissioned 1995]. H. L. Hunley built the Confederate submarine that sank with him on board before it engaged in combat. A subsequent Confederate submarine was built and named for him. Commanded by George Dixon, the CSS Hunley carried out the world's first submarine attack when it struck the [sloop-of-war] USS Housatonic in February1864. Currently in the fleet is the [Ticonderoga (CG-47) class Aegis cruiser] USS Chancellorsville (CG-62) [commissioned 1989], named for Lee's greatest victory over the U.S. Army. Chancellorsville also was the battle in which Gen. Thomas "Stonewall" Jackson was mortally wounded by friendly fire. The purpose of erecting monuments and naming U.S. ships after Confederates—enemies of the United States—seems to be to recognize their perceived status as noble warriors rather than to remember the cause for which they waged war: the dissolution of the United States to preserve the "peculiar institution" of human slavery. This view of history is not shared by millions of Americans who see the monuments to Confederates as glorifying, even justifying the "lost cause" and the enslavement of humans. Other ships have been named for enemies [of the United States], probably because they were considered "noble warriors" too. [The ballistic missile submarine] USS Tecumseh (SSBN-628) [commissioned 1964; decommissioned 1993] and [the harbor tug] USS Osceola (YTB-129) [commissioned 1938; sold for scrapping 1973] were named after American Indian leaders who fought wars against the United States. Regarding the Chancellorsville , the Navy states that the cruiser is The first U.S. Navy ship named for a Civil War battle fought just south of the Rappahannock and Rapidan Rivers in Virginia (1–5 May 1863). Gen. Robert E. Lee, CSA, who led the Confederate Army of Northern Virginia, held Gen. Joseph Hooker, USA, who commanded the Union Army and Department of the Potomac, in position while Lt. Gen. Thomas J. Jackson, CSA, enveloped the Union right flank, surprising and rolling up the Federal's right. Lee's victory, combined with the urgent need to relieve pressure on Vicksburg, Miss., prompted the South's thrust into Pennsylvania that summer, resulting in the pivotal Battle of Gettysburg. An August 16, 2017, press report states the following: As America churns through a bloody debate over the place Confederate monuments occupy in the modern day United States, a Navy cruiser named in honor of a Confederate Civil War victory is unlikely to see its named changed, a service official said Wednesday [August 16]. The guided-missile cruiser Chancellorsville [CG-62] was commissioned in 1989 and derives its name from an 1863 battle considered to be the greatest victory of Confederate Gen. Robert E. Lee.... But a Navy official speaking on the condition of anonymity Wednesday said that even though the Chancellorsville is named after a Confederate victory, the name comes from a battle, not an individual, and soldiers on both sides died. The week-long battle resulted in major casualties for both sides—13,000 Confederates and 17,000 Union troops, according to the National Parks [sic: Park] Service. The Navy official did say, however, that there remains a chance the ship's crest could be altered. The predominance of gray in the ship's crest speaks to "General Robert E. Lee's spectacular military strategies and his dominance in this battle," according to the ship's website. An inverted wreath also memorializes the Confederacy's second-best known general, Stonewall Jackson, who was mortally wounded in the battle. While the rupture of the country during the Civil War is reflected in the crest, it also features Jackson's order to "press on." "Maybe that is worth re-looking at or redoing," the official said. "There's a fine line." In recent years, the Navy on a few occasions has announced names for ships years before those ships were procured. Although announcing a name for a ship years before it is procured is not prohibited, doing so could deprive a future Secretary of the Navy (or, more broadly, a future Administration) of the opportunity to select a name for the ship. It could also deprive Congress of an opportunity to express its sense regarding potential names for a ship, and create a risk of assigning a name to a ship that eventually is not procured for some reason, a situation that could be viewed as potentially embarrassing to the Navy. As noted earlier, the July 2012 Navy report to Congress states the following: At the appropriate time—normally sometime after the ship has been either authorized or appropriated by Congress and before its keel laying or christening—the Secretary records his decision with a formal naming announcement. At the end of the above passage, there is a footnote (number 3) in the Navy report that states the following: Although there is no hard and fast rule, Secretaries most often name a ship after Congress has appropriated funds for its construction or approved its future construction in some way—such as authorization of either block buys or multi-year procurements of a specific number of ships. There are special cases, however, when Secretaries use their discretion to name ships before formal Congressional approval, such as when Secretary John Lehman announced the namesake for a new class of Aegis guided missile destroyers would be Admiral Arleigh Burke, several years before the ship was either authorized or appropriated. In connection with the quoted footnote passage immediately above, it can be noted that the lead ship of the DDG-51 class of destroyers was named for Arleigh Burke on November 5, 1982, about two years before the ship was authorized and fully funded. Recent examples of Navy ships whose names were announced more than two years before they were procured include the following: The destroyer Zumwalt (DDG-1000). On July 4, 2000, President Bill Clinton announced that DDG-1000, the lead ship in a new class of destroyers, would be named Zumwalt in honor of Admiral Elmo Zumwalt Jr., the Chief of Naval Operations from 1970 to 1974, who had died on January 2, 2000. At the time of the naming announcement, Congress was considering the Navy's proposed FY2001 budget, under which DDG-1000 was scheduled for authorization in FY2005, a budget that Congress would consider in 2004, which was then about four years in the future. The aircraft carrier Enterprise (CVN-80). As noted earlier, on December 1, 2012, the Navy announced that CVN-80, the third Gerald R. Ford (CVN-78) class aircraft carrier, would be named Enterprise . At the time of the announcement, CVN-80 was scheduled for procurement in FY2018, the budget for which Congress was to consider in 2017, which was then more than four years in the future. (CVN-80 was in fact procured in FY2018.) The ballistic missile submarine ( SSBN-826 ) Columbia . As noted earlier, on July 28, 2016, it was reported that the first Ohio replacement ballistic missile submarine (SSBN-826) will be named Columbia in honor of the District of Columbia. This ship is scheduled for procurement in FY2021, the budget for which Congress is to consider in 2020, which in July 2016 was about four years in the future. Three John Lewis (TAO- 205) class oilers. As noted earlier, on July 28, 2016, it was reported that the Navy would name the second through sixth John Lewis (TAO-205) class oilers (i.e., TAOs 206 through 210) for Harvey Milk, Earl Warren, Robert F. Kennedy, Lucy Stone, and Sojourner Truth, respectively. In 2016, these five ships were scheduled for procurement in FY2018, FY2019, FY2020, FY2021, and FY2022, respectively, the budgets for which Congress has considered or will consider in 2017, 2018, 2019, 2020, and 2021, respectively. Thus, using the procurement dates that were scheduled in 2016, the name for TAO-208 ( Robert F. Kennedy ) was announced about three years before it was to be procured, the name for TAO-209 ( Lucy Stone ) was announced about four years it was to be procured, and the name for TAO-210 ( Sojourner Truth ) was announced about five years before it was to be procured. As discussed in the CRS report on the TAO-205 class program, the first six ships in the TAO-205 class are being procured under a block buy contract that Congress authorized as part of its action on the FY2016 defense budget. The procurement of each ship under this contract remains subject to the availability of appropriations for that purpose. Members of the public are sometimes interested in having Navy ships named for their own states or cities, for earlier U.S. Navy ships (particularly those on which they or their relatives served), for battles in which they or their relatives participated, or for people they admire. Citizens with such an interest sometimes contact the Navy, the Department of Defense, or Congress seeking support for their proposals. An October 2008 news report, for example, suggested that a letter-writing campaign by New Hampshire elementary school students that began in January 2004 was instrumental in the Navy's decision in August 2004 to name a Virginia-class submarine after the state. The July 2012 Navy report to Congress states the following: In addition to receiving input and recommendations from the President and Congress, every Secretary of the Navy receives numerous requests from service members, citizens, interest groups, or individual members of Congress who want to name a ship in honor of a particular hometown, or State, or place, or hero, or famous ship. This means the "nomination" process is often fiercely contested as differing groups make the case that "their" ship name is the most fitting choice for a Secretary to make. Members of the public may also express their opposition to an announced naming decision. The July 2012 Navy report to Congress cites and discusses five recent examples of ship-naming decisions that were criticized by some observers: the destroyer DDG-1002 (named for President Lyndon Johnson), the Littoral Combat Ship LCS-10 (named for former Representative Gabrielle Giffords), the amphibious ship LPD-26 (named for late Representative John P. Murtha), the auxiliary ship TAKE-13 (named for Medgar Evers), and the auxiliary ship TAKE-14 (named for Cesar Chavez). Congress has long maintained an interest in how Navy ships are named, and has influenced or may have influenced pending Navy decisions on the naming of certain ships, including but not limited to the following: One source states that "[the aircraft carriers] CVN 72 and CVN 73 were named prior to their start [of construction], in part to preempt potential congressional pressure to name one of those ships for Admiral H.G. Rickover ([instead,] the [attack submarine] SSN 709 was named for the admiral)." There was a friendly rivalry of sorts in Congress between those who supported naming the aircraft carrier CVN-76 for President Truman and those who supported naming it for President Reagan; the issue was effectively resolved by a decision announced by President Clinton in February 1995 to name one carrier (CVN-75) for Truman and another (CVN-76) for Reagan. One press report suggests that the decision to name CVN-77 for President George H. W. Bush may have been influenced by a congressional suggestion. Section 1012 of the FY2007 John Warner National Defense Authorization Act ( H.R. 5122 / P.L. 109-364 of October 17, 2006), expressed the sense of the Congress that the aircraft carrier CVN-78 should be named for President Gerald R. Ford. The Navy announced on January 16, 2007, that CVN-78 would be named Gerald R. Ford . In the 111 th Congress, H.Res. 1505 , introduced on July 1, 2010, expressed the sense of the House of Representatives that the Secretary of the Navy should name the next appropriate naval ship in honor of John William Finn. The measure was not acted on after being referred to the House Armed Services Committee. On February 15, 2012, the Navy announced that DDG-113, an Arleigh Burke (DDG-51) class destroyer, would be named John Finn . Section 1012 of the FY2012 National Defense Authorization Act ( H.R. 1540 / P.L. 112-81 of December 31, 2011) expressed the sense of Congress that the Secretary of the Navy is encouraged to name the next available naval vessel after Rafael Peralta. On February 15, 2012, the Navy announced that DDG-113, an Arleigh Burke (DDG-51) class destroyer, would be named Rafael Peralta . The July 2012 Navy report to Congress states that every Secretary of the Navy, regardless of point of view [on how to name ships], is subject to a variety of outside influences when considering the best names to choose. The first among these comes from the President of the United States, under whose direction any Secretary works... Secretaries of the Navy must also consider the input of Congress.... Given the vital role Congress plays in maintaining the Navy-Marine Corps Team, any Secretary is sure to respect and consider its input when considering ships names. Sometimes, the Secretary must also balance or contend with differences of opinion between the President and Congress. The Navy suggests that congressional offices wishing to express support for proposals to name a Navy ship for a specific person, place, or thing contact the office of the Secretary of the Navy to make their support known. Congress may also pass legislation relating to ship names (see below). Congress can pass legislation regarding a ship-naming decision that has been announced by the Navy. Such legislation can express Congress's views regarding the Navy's announced decision, and if Congress so desires, can also suggest or direct the Navy to take some action. The following are three examples of such legislation: S.Res. 332 of the 115 th Congress is an example of a measure that appears to reflect support for an announced Navy ship-naming decision. This measure, introduced in the Senate on November 15, 2017, and considered and agreed to without amendment and with a preamble by unanimous consent the same day, summarizes the military career of Hershel "Woody" Williams and commemorates the christening of ESB-4, an expeditionary sea base ship named for Williams (see " Legislative Activity in 115th and 116th Congress .") H.Res. 1022 of the 111 th Congress is an example of a measure reflecting support for an announced Navy ship-naming decision. This measure, introduced on January 20, 2010, and passed by the House on February 4, 2010, congratulates the Navy on its decision to name a naval ship for Medgar Evers. H.Con.Res. 312 of the 97 th Congress is an example of a measure that appears to reflect disagreement with an announced Navy ship-naming decision. This measure expressed the sense of Congress that the Los Angeles (SSN-688) class attack submarine Corpus Christi (SSN-705) should be renamed, and that a nonlethal naval vessel should instead be named Corpus Christi . (Los Angeles-class attack submarines were named for cities, and SSN-705 had been named for Corpus Christi, TX.) H.Con.Res. 312 was introduced on April 21, 1982, and was referred to the Seapower and Strategic and Critical Materials subcommittee of the House Armed Services Committee on April 28, 1982. On May 10, 1982, the Navy modified the name of SSN-705 to City of Corpus Christi . On April 12, 2013, then-Secretary of the Navy Ray Mabus announced that LPD-27, a San Antonio (LPD-17) class amphibious ship, would be named for Portland, OR. LPD-27 is to be the third Navy ship to bear the name Portland. The first, a cruiser (CA-33), was named for Portland, ME. It was commissioned into service in February 1933, decommissioned in July 1946, and maintained in reserve status until struck from the Navy list in March 1959. The second, an amphibious ship (LSD-37), was named for both Portland, ME, and Portland, OR. It was commissioned into service in October 1970, decommissioned in October 2003, and stricken from the Naval Vessel Register in March 2004. An April 18, 2013, press release from Senator Angus King stated that "U.S. Senators Susan Collins and Angus King today sent a letter to Ray Mabus, the Secretary of the Navy, asking that the USS Portland [LPD-27], a new San Antonio-class amphibious transport dock ship named after the city of Portland, Oregon, also be named in honor of Portland, Maine, consistent with the long history and tradition of U.S. Navy ships bestowed with the name USS Portland." In reply, the Navy sent letters dated April 24, 2013, to Senators Collins and King that stated the following in part: In addition to [the ballistic missile submarine] USS MAINE (SSBN 743), Secretary [of the Navy Ray] Mabus recently honored the state of Marine through his naming of [the expeditionary fast transport ship] USNS MILLINOCKET (JHSV 3) [now called T-EPF 3] which was christened last weekend and will proudly represent our Nation as part of the fleet for decades to come. The Secretary of the Navy has tremendous appreciation for the state of Maine, its citizens and the incredible support provided by them to our Navy and our Nation. However, Oregon is the only state in our Nation that does not currently have a ship in the fleet named for the state, its cities or communities. Secretary Mabus named LPD 27 after Portland, Oregon, to correct that oversight and acknowledge the support and contributions made by the men and women of Portland and Oregon. As noted elsewhere in this report, on October 10, 2014, the Navy announced that it was naming the Virginia-class attack submarine SSN-793 for Oregon. A May 21, 2016, Navy blog post about the ship's christening states that "LPD-27 will be the third Navy ship named Portland, honoring both the Oregon seaport and Maine's largest city." That statement is not correct, as the Navy confirms that LPD-27 is named solely for Portland, OR. A July 5, 2017, Navy News Service report states correctly that "LPD 27 is named for the city of Portland, Oregon, and follows the World War II heavy cruiser CA 33 and the amphibious ship LSD 37 as the third U.S. Navy ship to bear the name Portland." LPD-27 is scheduled to be commissioned in Portland, OR, on April 21, 2018. Table 3 shows past enacted provisions going back to the 100 th Congress regarding future ship-naming decisions. All of these measures expressed the sense of the Congress (or of the Senate or House) about how a future Navy ship should be named. Table 4 shows past examples of proposed bills and amendments regarding future ship-naming decisions going back to the 93 rd Congress. Some of these measures expressed the sense of the Congress about how a Navy ship should be named, while others would mandate a certain name for a ship. Although few of these measures were acted on after being referred to committee, they all signaled congressional interest in how certain ships should be named, and thus may have influenced Navy decisions on these matters. S.Con.Res. 10 of the 115 th Congress was introduced in the Senate on March 21, 2017; no further actions for the measure are listed at Congress.gov. The text of S.Con.Res. 10 as introduced was as follows: CONCURRENT RESOLUTION Expressing the sense of Congress that the Secretary of the Navy should name the next nuclear powered submarine of the United States Navy the "USS Los Alamos". Whereas the people of Los Alamos and the Navy have a 74-year relationship that continues from the Manhattan Project through the creation of a nuclear Navy and into the current ocean-borne leg of the strategic nuclear triad of the United States; Whereas the contributions of the people of Los Alamos and surrounding communities allowed the Navy to keep its offensive edge from World War II, through the Cold War, continuing to the emerging conflicts as of the date of adoption of this resolution; Whereas Captain "Deke" Parsons was one of the first residents of Los Alamos and, along with Laureate Ramsey, oversaw the safe delivery, assembly and loading of the nuclear bomb that led to the surrender of Japan in World War II; Whereas the people of Los Alamos and surrounding communities played a critical role in designing the nuclear portion of the first nuclear weapon to enter the arsenal of the Navy, known as the Regulus, along with atomic depth bombs, torpedoes, rockets, and even next generation weapon systems like the B61–12 precision-guided nuclear bomb; Whereas the people of Los Alamos designed the warheads that armed the first generation Trident submarine-launched ballistic missiles of the Navy and the follow-on Trident II missile warheads used by the Navy; Whereas the research into nuclear energy conducted by Los Alamos during World War II advanced the technical basis for the development of the nuclear propulsion systems of the Navy used aboard Los Angeles, Seawolf, Ohio, and Virginia Class submarines along with multiple naval aircraft carriers today; Whereas the people of Los Alamos and Los Alamos National Laboratory host United States Naval Academy midshipmen every year to provide hands-on scientific and engineering experience working to solve real world challenges in national security, thereby directly contributing to the development of future Navy leadership; Whereas the people of Los Alamos carry the solemn responsibility to assess the sea-based nuclear deterrent carried aboard Navy fleet ballistic missile submarines; Whereas naming a submarine Los Alamos will recognize and continue to forge the longstanding relationship between the Navy and Los Alamos; Whereas the year 2018 will mark the 75th anniversary of Los Alamos National Laboratory; and Whereas the distinctive service and contributions from the people of Los Alamos to the Navy merits naming a vessel that embodies the heritage, service, fidelity, and achievements of the residents of Los Alamos and surrounding communities in partnership with the United States Navy: Now, therefore, be it Resolved by the Senate (the House of Representatives concurring), That it is the sense of the Congress that the Secretary of the Navy should name the next nuclear powered submarine of the United States Navy as the "USS Los Alamos". Appendix A. Executive Summary of July 2012 Navy Report to Congress This appendix reprints the executive summary of the July 2012 Navy report to Congress on the Navy's policies and practices for naming its ships. The text of the executive summary is as follows: Executive Summary This report is submitted in accordance with Section 1014 of P.L. 112-81 , National Defense Authorization Act (NDAA) for Fiscal Year 2012, dated 31 December 2011, which directs the Secretary of Defense to submit a report on "policies and practices of the Navy for naming vessels of the Navy." As required by the NDAA, this report: Includes a description of the current policies and practices of the Navy for naming vessels of the Navy, and a description of the extent to which theses policies and practices vary from historical policies and practices of the Navy for naming vessels of the Navy, and an explanation for such variances; Assesses the feasibility and advisability of establishing fixed policies for the naming of one or more classes of vessels of the Navy, and a statement of the policies recommended to apply to each class of vessels recommended to be covered by such fixed policies if the establishment of such fixed policies is considered feasible and advisable; and Identifies any other matter relating to the policies and practices of the Navy for naming vessels of the Navy that the Secretary of Defense considers appropriate. After examining the historical record in great detail, this report concludes: Current ship naming policies and practices fall well within the historic spectrum of policies and practices for naming vessels of the Navy, and are altogether consistent with ship naming customs and traditions. The establishment of fixed policies for the naming of one or more classes of vessels of the Navy would be highly inadvisable. There is no objective evidence to suggest that fixed policies would improve Navy ship naming policies and practices, which have worked well for over two centuries. In addition, the Department of the Navy used to routinely publish lists of current type naming rules for battle force ships, and update it as changes were made to them. At some point, this practice fell into disuse, leading to a general lack of knowledge about naming rules. To remedy this problem, the Naval History and Heritage Command will once again develop and publish a list of current type naming rules to help all Americans better understand why Secretaries of the Navy choose the ship names they do. This list will be updated as required.

 

 Report 2:
The U.S. Fourth National Climate Assessment, released in 2018, concluded that "the impacts of global climate change are already being felt in the United States and are projected to intensify in the future—but the severity of future impacts will depend largely on actions taken to reduce greenhouse g as [GHG] emissions and to adapt to the changes that will occur." Although a variety of efforts seeking to reduce GHG emissions are currently underway on the international and sub-national level, federal policymakers and stakeholders have different viewpoints over what to do, if anything, about future climate change and related impacts. Their views regarding climate change cover a wide range of perspectives. For example, some contend that climate change poses a "direct, existential threat" to human society and that nations must start making significant reductions in GHG emissions in order to avoid "dire effects." To support this argument, proponents of climate change mitigation highlight the evidence and conclusions from recent reports that are generally considered authoritative, including: 1. The Intergovernmental Panel on Climate Change, Global W arming of 1.5°C , 2018; and 2. The U.S. Global Change Research Program, Fourth National Climate Assessment , Volume II: Impacts, Risks, and Adaptation in the United States , 2018. On the other hand, some question whether there are sufficient risks of climate change to merit a federal program requiring GHG emission reductions. In addition, others argue that a unilateral approach to climate change by the United States could disproportionately impact domestic industries while achieving minimal results in global climate change mitigation. If Congress were to consider establishing a program to reduce GHG emissions, one option would be to apply a tax or fee on GHG emissions or the inputs that produce them. This type of approach is commonly called a carbon tax or a GHG emissions fee (see "Terminology Issues: A Carbon Tax or an Emissions Fee?"). This report does not compare and analyze the multiple policy tools available to Congress that could address climate change (see text box "Other Policy Options for Addressing GHG Emissions"). This report focuses on the policy considerations and potential impacts of using a carbon tax or GHG emissions fee to control GHG emissions. The key human-related GHG is CO 2 , which is generated primarily through the combustion of fossil fuels: coal, oil, and natural gas. In 2016, fossil fuel combustion accounted for 94% of U.S. CO 2 emissions and 76% of U.S. GHG emissions. A carbon tax could apply either directly to GHG emissions or to the materials—based on their carbon contents—that ultimately generate the emissions (i.e., "emissions inputs"). A carbon price on emissions or their emissions inputs—mainly fossil fuels—would increase the relative price of the more carbon-intensive energy sources, particularly coal. This result could spur innovation in less carbon-intensive technologies (e.g., renewable energy, nuclear power, carbon capture and sequestration [CCS]) and stimulate other behavior that may decrease emissions, such as efficiency improvements. The energy price increases could also have both economy-wide impacts and negative effects on specific industries and particular demographic groups. A carbon tax approach has received some attention and debate in recent years. In the 115 th Congress, Members introduced nine carbon tax or fee proposals. Outside of Congress, the Climate Leadership Council—a bipartisan group of former policymakers and industry leaders—published a conceptual carbon tax approach in 2017 that generated some interest. Some of the industry leaders on the council represent major energy companies, including Shell, BP, and ExxonMobil. On the other hand, many Members have expressed their opposition to a carbon tax. Starting in the 112 th Congress and going through the 115 th Congress, Members have introduced resolutions in both the House and Senate expressing the view that a carbon tax is not in the economic interests of the United States. In 2018, the House passed a resolution "expressing the sense of Congress that a carbon tax would be detrimental to the United States economy" ( H.Con.Res. 119 ). An analogous resolution was not introduced in the Senate in the 115 th Congress. The first section of this report examines carbon tax design issues, including the point of taxation, the rate of taxation, and potential border carbon adjustments. The second section discusses issues related to the distribution of carbon tax revenues. The third section discusses additional considerations associated with a carbon tax program, including estimates of GHG emissions, federal revenue, and fossil fuel prices and changes in energy use. The fourth section provides concluding observations. If policymakers decide to establish a carbon tax system, Congress would face several key design decisions, including the point of taxation—where to impose the tax and what to tax—the rate of taxation, and whether and/or how to address imported carbon-intensive materials. Alternatively, Congress could direct one or more federal agencies to determine these design features through a rulemaking procedure. Although a few of the GHG emission reduction proposals in prior Congresses delegated such authority to an agency, such as the U.S. Environmental Protection Agency (EPA), all of the proposals since the 111 th Congress have included some degree of design details in the statutory language. (A later section discusses carbon tax revenue application considerations.) The point of taxation would determine which entities would be required to (1) make tax payments based on emissions or emission inputs, such as fossil fuels, (2) monitor emissions or emission inputs, and (3) maintain records of relevant activities and transactions. This section provides some considerations for policymakers deciding which GHG emissions and/or emission sources to cover in a carbon tax system. Throughout the U.S. economy, millions of discrete sources generate GHG emissions: power plants, industrial facilities, motor vehicles, households, commercial buildings, livestock, etc. Administrative costs and challenges would likely increase with a broader scope of an emissions tax. A carbon tax may apply to CO 2 emissions alone, which account for most U.S. GHG emissions, or to multiple GHGs. Carbon tax proposals that apply only to CO 2 generally attach a price to a metric ton of CO 2 emissions (mtCO 2 ). Some sources emit non-CO 2 GHGs, such as methane, nitrous oxides, and sulfur hexafluoride. GHG emissions from these sources could be addressed by attaching a price to a metric ton of CO 2 emissions-equivalent (mtCO 2 e). This term of measure is used because GHGs vary by global warming potential (GWP). At these sources, the determined GWP values would be an important issue. Policymakers may consider limiting the tax to sectors or sources that emit above a certain percentage of total U.S. GHG emissions, many of which currently report their emissions to the government. For more than 20 years, monitoring devices or systems have been installed in smokestacks of most large facilities, such as power plants, which are required to periodically report emissions data to EPA. In addition, since 2010, EPA has collected annual emissions data from approximately 8,000 facilities that directly release above certain amounts of GHG emissions. Using these established monitoring frameworks, policymakers could employ a "downstream" approach, applying a carbon tax at the point where the GHGs from these facilities are released to the atmosphere. Alternatively, the tax could be applied to reliable proxies for emissions, such as emission inputs. For example, the carbon content of fossil fuels—coal, natural gas, petroleum—can serve as a proxy for the emissions released when the fuels are combusted. Applying a tax on emission inputs allows for the consideration of various points of taxation. For instance, emission inputs could be taxed at "upstream" (e.g., wells) or "midstream" stages in that process (e.g., refineries), the latter allowing for potential tax administration advantages that may be provided by specific infrastructure chokepoints in the fossil fuel market. For example, with respect to petroleum, the number of upstream sources—wells that produce crude oil—is over 445,000, but the number of midstream sources—facilities that refine crude oil—is only 137. Table A-1 (in Appendix A) lists the top GHG emission sources in the United States. These sources combined to account for approximately 95% of U.S. GHG emissions in 2016. Table A-1 identifies the number of entities for each source category (e.g., number of coal mines, number of steel production facilities) and the percentage of total U.S. GHG emissions the category contributes. In the case of fossil fuel combustion—which accounted for 76% of total U.S. GHG emissions—the table provides several options for segmenting the universe of sources if policymakers choose to implement a carbon tax. It identifies the number of entities that might be subject to the carbon tax under a particular option (pending any exclusions). For example, policymakers could address fossil fuel combustion emissions by applying a carbon tax to fossil fuels (based on their carbon content) at the following entities, which include both upstream and midstream infrastructure chokepoints: 137 petroleum refineries (based on 2017 data) and 166 petroleum importers (based on 2018 data); 671 coal mines and eight companies supplying imported coal (based on 2017 data); and 1,679 entities that report natural gas deliveries to the Energy Information Administration (EIA) on Form EIA-176 and 123 natural gas fractionators (based on 2016 data). Some of the above points of taxation might take advantage of the administrative frameworks for existing federal excise taxes. For example, a per-barrel federal excise tax on crude oil at the refinery supports the Oil Spill Liability Trust Fund. An excise tax on the sale or use of coal supports the Black Lung Disability Trust Fund. A central policy choice when establishing a price on GHG emissions is the rate of the carbon tax. Several approaches, which are discussed below, could inform the decision. One approach would set the carbon tax rate at a level or pathway—based on modeling estimates—that would achieve a specific GHG emissions target. For example, a 2018 study estimated the carbon tax rate needed to meet the U.S. GHG emission reduction targets established under the 2015 Paris Agreement: 26%-28% below 2005 net GHG emission levels by 2025. The study found that a constant tax rate of $43/ton starting in 2019 would meet the 2025 reduction target. Emissions reduction estimates from carbon tax programs are based on multiple assumptions. Accordingly, such estimates provide different tax rates needed to meet a particular emissions target depending on these assumptions. See " Impacts on GHG Emission Levels " for selected analyses of emission reductions for a given carbon price and rate of price increase. Under another approach, policymakers could base the carbon tax rate on the estimated marginal net benefits associated with reduced CO 2 emissions. The net benefits would be the avoided net damages (i.e., costs) of climate change. The estimates of net benefits of avoided emissions often rely on analyses of the social cost of carbon (SC-CO 2 ) or the social cost of greenhouse gases (SC-GHG ). Therefore, policymakers could use SC-CO 2 measurements—as the basis for an estimate of the net benefits of a marginal change in emissions—to set the rate of a carbon tax or emissions fee. One potential challenge of relying on SC-CO 2 estimates to set a carbon fee are methodological concerns. For example, the existing estimates in peer-reviewed research cover a wide range. In addition, some argue that the underlying simulation models for estimating the SC-CO 2 values are insufficient. For any level of emissions, the projected increase in global average temperature may cover multiple degrees Fahrenheit, and other measures of climate change, such as precipitation patterns, may encompass directional uncertainties. No estimates of impacts are comprehensive at this time, and many of the risks are difficult to estimate and value. When valuing the SC-CO 2 , analysts encounter a range of views on methods and assumptions, and establishing study parameters may be challenging. For example, estimates of the monetary values of climate change impacts may be difficult or controversial to estimate, such as the monetary values associated with human deaths or sickness. A related framework question is whether to include global climate impacts or just domestic impacts. In addition, the element of time in climate change impacts particularly complicates the valuation. The fact that many impacts of climate change will occur in the distant future requires consideration of society's willingness to pay in the near term to reduce emissions that would cause future damages, mostly to future generations. To take time into account, economists discount future values to a calculated "present value." Economists do not agree on the appropriate discount rate(s) to use for a multi-generational, largely nonmarket issue such as human-induced climate change. The choice of discount rate can significantly increase or decrease values of the SC-CO 2 . A low discount rate would give greater value today to future impacts than would a higher discount rate. High discount rates can reduce the value today of future climate change impacts to a small fraction of their undiscounted values. A high discount rate would recommend applying fewer of today's resources to addressing climate change impacts in the future. Since 2008, federal agencies have used SC-CO 2 estimates in dozens of final rulemakings as a method to estimate the net benefits of abating CO 2 emissions. An Interagency Working Group prepared SC-CO 2 estimates, which were updated over time and subjected to expert and public comment. On March 28, 2017, President Trump issued Executive Order 13783, "Promoting Energy Independence and Economic Growth," which effectively withdrew the federal SC-CO 2 estimates. Nonetheless, federal agencies have used new, interim values generated by EPA in 2017, modified from the withdrawn technical support documents, in regulatory and other decisions. Legislation could set a carbon price citing any of these SC-CO 2 values or others available from nonfederal researchers or prescribe methods for estimating new ones. Using SC-CO 2 estimates to set the tax rate would involve a cost-benefit framework. Although many posit that a cost-benefit framework remains the best option, some economists argue that a cost-benefit framework may be inappropriate for climate change policy for these reasons Many experts expect climate change—and policies to address it—to cause nonmarginal changes to economies and ecosystems. The changes are expected to increase disproportionately with incremental climate change with a potential for crossing critical "tipping points" after which systems change dramatically and rapidly. Climate change impacts are multi-generational, and uncertainty and disagreement exists about whether and how to assign a present value to social costs and benefits over generations. Some impacts from climate change may be irreversible on the timescale of human civilizations, such as melting of major ice sheets in Antarctica or Greenland. Policymakers might consider a carbon tax as a fiscal tool to help reduce the federal deficit, reduce other taxes, or pay for specific programs that may or may not be related to climate change policy. In addition, some have proposed a phased-in approach, setting a rate that is initially lower but increases at an announced or adjustable rate either for a fixed period or indefinitely. Advantages of this approach include providing an opportunity for consumers and investors to adjust their behavior before the higher tax rates go into effect, such as purchasing more energy efficient appliances or investing in low-emissions technologies. Phasing in a carbon tax, however, could delay climate-related benefits. If Congress finds agreement in principle on carbon pricing, the rate(s) could emerge from the process of reaching political agreement. Elements that might be considered include the options described above or consideration of the magnitude of overall economic impact; impacts on certain economic sectors, regions, or population groups; timing to motivate and allow an orderly transition to a lower-GHG economy; or other factors. Many stakeholders have voiced concerns over how a U.S. carbon price system would interact with policies in other nations, particularly if the United States were to enact a carbon tax system that covers more sources or is more stringent than enacted elsewhere. A central concern is that a U.S. carbon tax could raise U.S. prices more than the prices of goods manufactured abroad, potentially creating a competitive disadvantage for some domestic businesses. Certain businesses may become less profitable, lose market share, and reduce jobs. The industries generally expected to experience disproportionate impacts under a U.S. carbon tax are often described as "emission-intensive, trade-exposed" industries. An industry's CO 2 emission intensity is a function of both direct CO 2 emissions from its manufacturing process (e.g., CO 2 from cement or steel production) and indirect CO 2 emissions from the inputs to the manufacturing process (e.g., electricity, natural gas). Such industries are likely to experience greater cost increases than less carbon intensive industries, all else being equal. In general, trade-exposed industries are those that face greater international competition compared to other domestic industries. A carbon tax could present a particular challenge for these industries, because they might be less able to pass along the tax in the form of higher prices, because they may lose global market share—and jobs—to competitors in countries lacking comparable carbon policies. Policymakers might consider approaches to mitigate these potential economic impacts in several ways. One approach that has received interest in recent years is a border adjustment mechanism, which is often described as a border carbon adjustment (BCA) in the carbon tax context. A BCA would apply a tariff to emission-intensive, imported goods such as steel, aluminum, cement, and certain chemicals. Each of the carbon price proposals in the 115 th Congress would have established a BCA to address emission-intensive imports. Another rationale for adding a BCA to a carbon tax system is the possibility that it would encourage other nations to adopt comparable carbon price policies. Many of the recently proposed BCA mechanisms allow for exemptions for nations with comparable programs. To date, no nations have implemented a BCA as part of their climate change policies. Establishing an economically efficient BCA would likely present substantial challenges. For example, policymakers must decide which goods and/or industries would be covered by a BCA and how the adjustment program would assess the comparability of varied climate-related policies in other nations. In addition, accurately determining and verifying the volume of GHG emissions embodied in a particular imported product would be data intensive and challenging. To alleviate some of the measurement complexity, policymakers could limit the program to selected industries and apply default values and assumptions to particular manufacturing processes. However, this simplified approach could result in less accurate import price adjustments, which could potentially affect the accuracy of GHG emission reductions achieved by the carbon tax program. Another option would be to allow companies to provide measured, independently verified emissions data as an alternative to default values. In addition, the border adjustment approach would likely raise concerns of violating international trade rules. Further, some researchers have highlighted the potential for unintended consequences from a BCA. For example, some studies have found that a border adjustment may lead to lower net exports than the carbon price alone, due to the adjustment's terms-of-trade effect on U.S. currency. These issues are beyond the scope of this report, but some of the concerns may be lessened to some degree if a larger number of nations establish comparable emission reduction policies, as many have agreed to do under the Paris Agreement. Another possible rationale for a BCA is to address the concern of "emissions leakage" (or "carbon leakage"). Emissions leakage "occurs when economic activity is shifted as a result of the emission control regulation [e.g., a carbon tax program] and, as a result, emission abatement achieved in one location that is subject to emission control regulation is [diminished] by increased emissions in unregulated locations." The concern of emissions leakage has been central in the debate over whether the United States (or any nation) should unilaterally address GHG emissions. A BCA may diminish the potential for emissions leakage by reducing the incentive to shift economic activity to a nation without a comparable carbon tax. However, some recent studies raise questions regarding the degree to which emissions leakage would be a concern under a unilateral U.S. carbon tax. Although a tax may be levied on fossil fuels or GHG emission sources at various points in the economy, the carbon tax impacts may be experienced elsewhere. Policymakers have multiple options to address these expected impacts. Policymakers would face challenging decisions regarding the distribution of the new carbon tax revenues. As discussed below, some economic analyses indicate that certain distributions of tax revenue—depending on the level of the tax—would have a greater economic impact than the direct effects from the tax or fee on GHG emissions. Carbon tax revenues could be treated as general fund revenue without a dedication to a specific purpose in the enacting legislation (i.e., subject to the annual appropriations process), or policymakers could state that the new revenues would support deficit (or debt) reduction. Alternatively, the enacting legislation could return the tax revenue to the economy in some manner, sometimes called "revenue recycling." All of the carbon tax legislative proposals in recent Congresses have proposed some manner of revenue recycling, specifically directing the carbon tax revenue to support specific policy objectives. Carbon tax revenues may be used to support a variety of policy goals. When deciding how to allocate the new revenue stream, policymakers would likely encounter trade-offs among objectives, including: reducing the economy-wide costs resulting from a carbon tax program; alleviating the costs borne by subgroups in the U.S. population, particularly low-income households and/or communities most dependent on carbon-intensive economic activity; and supporting specific policy objectives, such as domestic employment, climate change adaptation, energy efficiency, technological advance, energy diversity, or federal deficit reduction, among others. In general, economic carbon tax studies have found that the relative ranking of revenue recycling options to mitigate the economy-wide impacts is generally the opposite of the relative ranking for alleviating distributional impacts. The contrasting relative rankings highlight a central tradeoff policymakers would face when deciding how to allocate carbon tax revenues. The following sections discuss these trade-offs and some of the revenue application options that have received attention in recent years. A large body of economic literature has examined the economic impacts of hypothetical carbon tax programs, particularly the impacts of using the carbon tax revenues for different purposes. Many of the economic studies cited below were prepared prior to the enactment of the Tax Cuts and Jobs Act (TCJA, P.L. 115-97 ). Signed by President Trump in December 2017, the act changed various elements of the U.S. federal tax system. In particular, the act lowered the corporate income tax rate from 35% to 21%. As discussed below, adjusting the corporate income tax rate is one of the central policy options generally considered in carbon tax economic literature both before and after enactment of P.L. 115-97 . Based on a selected review of the economic literature that includes the tax code changes in P.L. 115-97 , the central conclusions from carbon tax literature regarding revenue recycling appear to be largely unchanged. A primary concern with a carbon tax is the potential economy-wide costs that may result. Generally, a tax or fee on GHG emissions or the fuels that generate them would increase certain energy prices, namely fossil fuels, in the near- to medium-term as well as the prices of goods and services produced using these materials, like electricity. This outcome is inherent to the carbon tax, as its purpose is to increase the relative price of the more carbon-intensive energy sources compared to less carbon-intensive alternatives, encourage innovation in less carbon-intensive technologies, and promote other activity (e.g., energy efficiency) that may decrease emissions. These expected outcomes will have some economy-wide impacts. Ultimately, the economy-wide effects would depend on a number of factors, including, but not limited to, the magnitude and scope of the carbon tax and, most importantly, use of the ensuing revenues. Economy-wide costs (referred to as macroeconomic costs) are often measured in terms of changes in projected gross domestic product (GDP) or another societal-scale metric, such as economic welfare. The magnitude of macroeconomic impacts from a carbon tax has been a subject of debate among policymakers and stakeholders. In addition, results of economy-wide impacts will not include comparisons of impacts to different subpopulations or geographic regions, which may be of interest to policymakers. Multiple economic studies and models have examined and compared various options for addressing the economy-wide impacts that may result from a carbon tax. One option for reducing the economic cost of a carbon tax is using the revenue to reduce existing taxes, such as those on labor, income, and investment. Economists generally describe such taxes as distortionary, because the taxes discourage economically beneficial activity, such as employment and investment. Another option for policymakers is to use the tax revenues to address the national debt. Fewer studies have examined deficit reduction scenarios, because "modeling the effects of budget deficits is much more difficult than modeling the effects of tax cuts." Some studies have concluded that using tax revenues for this purpose would help alleviate economy-wide costs from a carbon tax because of the reduced need to impose distortionary taxes in the future. These studies indicate that the economy-wide benefit would be delayed and its realization assumes policymakers would, sometime in the future, address the deficit by raising taxes. Many recent legislative proposals would distribute the carbon tax revenue back to households in lump-sum payments. Policymakers have generally included this carbon tax revenue application to address distribution impacts (discussed below). These payments could take multiple forms. Economic analyses typically assume an equal payment to individuals or households regardless of their income or location or the effects of the carbon price on them individually. Alternatively, payments could be targeted or scaled to different segments of the population. Among the options mentioned above, economic studies indicate that using carbon tax revenues to offset reductions in existing, distortionary taxes would be the most economically efficient use of the revenues and yield the greatest benefit to the economy overall. This concept is sometimes referred to as a "tax swap." Using carbon tax or fee revenues to offset other distortionary taxes (e.g., labor or capital) may yield a "double-dividend," which includes: reduced GHG emissions; and reduced market distortions by reducing other distortionary taxes, such as investment or income. The economic models that examine the economic impacts of a carbon tax differ in their frameworks and underlying assumptions and often include multiple scenarios involving different uses of carbon tax revenue. In general, the economic models find that certain revenue recycling options may reduce the economy-wide carbon tax impacts but may not eliminate them entirely. Some studies cite particular economic modeling scenarios in which a carbon tax with certain revenue recycling applications would produce a net increase in GDP or economic welfare compared to a baseline scenario. These results indicate that, in certain modeling conditions, the economic improvements gained by reducing existing distortionary taxes would be greater than the costs imposed by the new carbon tax (without including the intended climate benefits of the policy). For example, results from a 2018 study demonstrated a net increase in GDP, compared to baseline conditions, when carbon tax revenues were used to finance proportionate reductions in labor tax rates (payroll tax). In general, the economic carbon tax studies usually agree on the relative ranking of revenue recycling options in terms of their ability to mitigate the economy-wide impacts of a carbon tax program. The studies indicate that the approaches that use carbon tax revenue to proportionately lower existing tax rates are able to mitigate more of the carbon tax economy-wide costs than using the revenue to provide a lump-sum distribution to individuals or households. Researchers prepared multiple carbon tax analyses prior to the enactment of the TCJA in 2017 that estimated the magnitude GDP impacts. As with other estimates relating to carbon tax impacts, the results depend on the scope of the carbon tax, underlying assumptions in the analytical model, and the terms of measurement: Some estimates measure GDP growth rates; others measure actual GDP. Figure 1 illustrates the modeled GDP results from a 2018 carbon tax analysis that includes the changes made by the TCJA. This study assessed the GDP impacts under a $50/mtCO 2 e carbon tax (starting in 2020 and increasing by 2% annually) that would apply to CO 2 emissions from fossil fuel combustion and methane emissions from fossil fuel production activities. The figure compares projected GDP impacts under a baseline scenario (i.e., no carbon tax) with three carbon tax revenue applications: a payroll tax rate reduction tax swap, a lump-sum distribution to households, and a scenario that would use tax revenue to reduce the national debt for 10 years and then use revenues for a lump-sum distribution to households. The figure projects GDP impacts in 2020, 2024, 2029, and 2039. As the figure indicates, the payroll tax rate scenario would result in a 0.1% loss of GDP in the first year (2020), but would yield GDP gains in subsequent years compared to baseline. The lump-sum distribution approach would yield GDP losses each year, ranging from 0.3% to 0.4% below the projected baseline. The deficit reduction approach would yield a range of GDP losses in the first 10 years—ranging from 0.4% to 0.04%—but would yield a GDP gain in 2039 (if not before), compared to baseline. Opponents of a carbon tax approach often highlight the GDP losses that would result from a carbon tax. Policymakers and stakeholders may have different perspectives regarding whether the magnitude of the GDP impacts are significant. In addition, GDP impact estimates may be presented in several ways. For example, one could compare the differences in GDP value for a particular year between carbon tax scenarios and a baseline scenario. This approach is employed in the above figure. Alternatively, one could present the GDP losses with a cumulative measure. For instance, if one were to add up the annual GDP losses (for example, over a 10-year period) from the lump-sum scenario compared to the baseline scenario, the resulting sum would be much larger. These types of calculations would require assumptions about annual GDP growth rates. Some may point out that the GDP impact estimates do not account for the environmental and public health benefits for reducing GHG emissions and that the GDP projections should be compared with the climate benefits achieved from the program as well as the estimated costs of taking no action. As discussed above, estimates of climate-related benefits and costs often contain considerable uncertainty and have generated debate in recent years. Many economic analyses have found that a carbon tax (before revenue recycling) would produce a regressive outcome among households, with lower-income households facing a larger impact from the tax than higher-income households. However, "the degree to which a carbon tax is found to disproportionately burden low-income households varies across studies, based on the metrics against which analysts measure costs." Entities that pay the carbon tax may pass its costs back to fuel producers or forward to fuel consumers. If entities pass the costs forward, consumers would face higher prices for fuels and electricity and carbon-intensive products. When the carbon tax is passed forward to consumers, lower-income households in particular would likely face a disproportionate impact (i.e., regressive outcome), because a larger percentage of their income is used to pay for energy needs, such as electricity, gasoline, or home heating oil. Many economic analyses of carbon price scenarios assume that the vast majority (if not all) of the carbon tax impact is passed forward to consumers, leading to a regressive outcome. On the other hand, if entities pass the costs backward to producers, the tax impacts would fall on labor through reduced wages or owners of capital through reduced returns on investment. Economic models that assume this outcome produce more progressive results (absent revenue recycling), with lower-income households experiencing smaller impacts than higher-income households. The economic analyses appear to agree that the distributional effects among households (i.e., regressive vs. progressive) of a carbon tax program would be largely dependent on how the carbon tax revenues were used. A number of economic studies have used models to estimate the impacts of a carbon tax across households under several revenue distribution scenarios. The results vary because the studies use different modeling frameworks, carbon tax rates and scopes, underlying assumptions, and ways to measure impacts. For example, a 2018 study assessed the impacts to household income for different household quintiles under a carbon tax of $50/mtCO 2 e, starting in 2020. This study examined four revenue distribution scenarios: 1. reduce federal deficit, 2. reduce corporate income tax rate, 3. reduce payroll tax rate, and 4. provide a per-capita rebate to households. This report highlights this study, because it includes carbon tax revenue applications that have generated interest in recent years. In addition, this analysis was prepared after the 2017 tax rate changes in P.L. 115-97 . Figure 2 illustrates the modeled results, which the study measured as percentage reductions to household income. Thus, negative percentages illustrated in the figure are gains to household income. The per-capita rebate approach provides the most progressive result, yielding a net benefit for the bottom three household quintiles but a net loss for the top quintile. The fourth quintile impact is zero. By comparison, the other approaches produce varying degrees of regressive outcomes while providing a net gain for wealthier groups in two particular instances. Of the four options, the payroll tax rate reduction approach estimates the smallest variance between the income quintiles, ranging from a 0.5% loss for the lowest quintile to a 0.2% gain for the fourth quintile. The fifth quintile impact is zero. The relative ranking among options for progressivity is generally the opposite of the relative ranking for mitigating economy-wide impacts. Other economic analyses have found similar relative rankings of revenue recycling options. The contrasting rankings highlight a central tradeoff policymakers would face when deciding how to allocate carbon tax revenues. Policymakers could allot some portion of the revenues to partially support both objectives. In a 2018 carbon tax study, economic modelers assessed a scenario in which a portion of the revenue was used to offset the welfare impacts for the lowest-income household quintile and the remaining revenue supported reductions in capital tax rates. The study's models estimated that a carbon tax's impacts on the lowest-income household quintile could be counteracted with approximately 10% of the revenue. This would allow for 90% of the revenue to be used to reduce capital tax rates and thus address the economy-wide impacts from the carbon tax. As discussed above, a carbon tax is projected to disproportionately impact certain industries, particularly those that are described as "emission-intensive, trade-exposed industries." To address these concerns, many of the recent carbon tax legislative proposals have included design mechanisms that would attach a carbon price to certain imported materials and products (see " Border Carbon Adjustments "). Another approach to addressing the competitiveness concerns of domestic industries would involve distributing a portion of the carbon tax revenues to emission-intensive, trade-exposed industries as rebates based on their output. Output rebate proposals generally determine rebate amounts by measuring emissions intensity at the relevant sector level or by a benchmark that would encourage facilities to reduce their emissions intensity. These rebates could be phased out over time or continue until other nations adopt comparable carbon price policies. Under a carbon tax system in Canada, which is scheduled to take effect in 2019, industries will be subject to an "output-based pricing system." Some contend that the data and administrative resources necessary to implement such a program would be substantial. A carbon tax system is also expected to disproportionately impact fossil fuel industries and the communities that rely on their employment. In particular, coal-mining communities are expected to experience substantial impacts based on the coal production declines predicted in carbon tax analyses. For example, one model estimates that under a $50/mtCO 2 e carbon tax, annual U.S. coal production would decline by almost 80% in 2030 compared to a reference case. Policymakers may consider supporting worker transition or community transition assistance to help mitigate the economic impacts. Several of the recent carbon tax proposals would have devoted carbon tax revenues for this objective. Policymakers may also consider using the carbon tax revenues to provide funding to support a range of objectives, which may include policy goals that are not directly related to climate change. Some options are identified below, and many have been included in recent legislative proposals or in state GHG mitigation programs that raise revenues: Technology development and deployment: Efforts to reduce the costs of emission mitigation technologies—particularly carbon capture, utilization, and sequestration—are often considered in carbon tax programs, and Congress has funded such programs in other legislation. Energy efficiency programs: Although a carbon tax would likely stimulate energy efficiency to some degree, Congress may consider using the revenues to provide additional incentives and/or technical assistance, particularly to encourage households and small businesses to increase efficiency, which would also reduce the effects of the tax on their energy bills. States in the Regional Greenhouse Gas Initiative (RGGI) have used revenues from the program to support efficiency improvements, among other objectives. Biological sequestration: Trees, plants, and soils sequester carbon, removing it from the earth's atmosphere. Revenues could be used to promote carbon sequestration efforts, particularly forestry or agricultural activities, which would supplement the GHG reductions of the carbon tax. Adaptation to climate change: Regardless of emission reduction efforts taken today, climatic changes are expected due to the ongoing accumulation of GHGs in the atmosphere. Therefore, some advocate using revenues to reduce potential damage—domestically and internationally—of a changing climate. Deficit reduction: The possible contribution of a carbon tax to deficit reduction would depend on the magnitude and scope of the carbon tax, various market factors, and assumptions about the size of the deficit. Some carbon tax proposals in recent congressional sessions would have allotted a portion of revenues for deficit reduction. Infrastructure funding: Some recent proposals have provided funding for infrastructure projects. This objective could be combined with funding for adaptation activities. Multiple economic studies have estimated the emission reductions that particular carbon tax designs could achieve. Economic models provide estimates based on the best information available at the time. Comparing results from different studies is problematic, because the studies' scenarios differ in multiple ways, including the tax rate, start date, scope of the program, assumptions about economic growth and technological advances, and assumptions about other federal and state policies and their effects. A 2018 study avoided some of these comparison difficulties by inviting modeling teams to analyze a coordinated set of scenarios. The 2018 Stanford Energy Modeling Forum study ("EMF 32") assembled 11 modeling teams to analyze the economic impacts of four carbon tax scenarios starting in 2020: a $25/metric ton and $50/metric ton carbon tax, increasing annually by 1% and 5%. Within each of these carbon price frameworks, the models ran separate revenue distribution scenarios: a reduction in labor tax rates, a reduction in capital tax rates, and household rebates. Figure 3 illustrates the study's estimates of CO 2 emissions from fossil fuel combustion. The red lines in the figure display the average values for the 11 models. The shaded areas illustrate the range of results, highlighting the uncertainties in emission reduction estimates. Based on these results, the study authors concluded that each of the tax rate scenarios would likely achieve the U.S. CO 2 emission reduction targets under the Paris Agreement. As Figure 3 indicates, a carbon tax or emissions fee could be set with the expectation that it would achieve an emissions reduction target, but the resulting level of emissions would be uncertain. The uncertainty of resulting emissions may lead some stakeholders to disfavor a carbon tax or fee option to control GHG emissions. Although uncertain emissions are inherent with a carbon tax approach, Congress could employ certain design elements to enhance the emission control certainty. For example, the existing GHG emission reporting data could be used to track the impact and performance of a carbon price. If policymakers determine that emission reduction is not occurring at a desired pace, the price could be amended. Legislation could establish the conditions and process by which price changes could occur. Some may argue that adjusting the carbon price to reflect actual emissions performance would undermine the benefits of price certainty. Others may point out that unplanned adjustments to the carbon price could be politically unpalatable. For example, it may be difficult for policymakers to increase the tax rate, especially during periods of high energy prices. Some have suggested that Congress authorize an independent board or agency with the mandate to modify the tax rate administratively in order to meet pre-determined emission reduction objectives. Although this approach would likely improve emission certainty, long-term price certainty may be sacrificed to some degree, depending on the authority of the delegated entity to adjust the tax rate. Some would argue that potential year-to-year emission variations under a carbon tax would not undermine efforts to control climate change so long as long-term emission goals are achieved. Indeed, they would assert that annual emission fluctuations are preferable to price volatility that could result from an emissions cap program. They support their preference for price control by suggesting that CO 2 generates damages through its overall accumulation as concentrations in the atmosphere, not its annual flow. A potential concern of a carbon tax is whether it would be effective in reducing GHG emissions in all of its covered sectors, particularly emissions in the transportation sector. As of 2016, the transportation sector contributes the largest percentage (36%) of CO 2 emissions from fossil fuel combustion, with electric power second at 35%. Carbon tax analyses generally agree that the majority of the emission reductions resulting from a carbon tax program would occur in the electricity sector. By comparison, economic models generally conclude that a carbon tax would have much less of an impact on emissions in the transportation sector. Several factors explain this projected outcome. The transportation sector offers fewer opportunities to switch to less carbon-intensive fuels in the short term than does the electric power sector, which can displace coal with natural gas relatively quickly. In addition, short-term emission changes in the transportation sector are largely influenced by changes in driving demand, which has historically been relatively insensitive to gasoline price increases. Based on these projected outcomes, some may contend that to achieve deeper, long-term reductions in total GHG emissions, policymakers would need to complement a carbon tax with other programs, such as vehicle technology standards (e.g., Corporate Average Fuel Economy, CAFE) or fuel performance standards, among other options. The quantity of revenues generated under a carbon tax system depend on the program's design features, namely the tax base and rate, as well as such independent factors as prices in global energy markets. They would also depend on how covered emission sources respond to the carbon price, for example by adopting alternative technologies or changing behavior. Several carbon tax studies have prepared revenue estimates, which are presented in Table 1 . From a public finance perspective, a carbon tax may not be a reliable source of long-term funding, because a primary goal of the carbon tax is to reduce its tax base—GHG emissions. The estimates in Table 1 project carbon tax revenue values in 2020. Multiple studies have projected carbon tax revenue trajectories beyond 2020. In the 2018 EMF 32 study, all but one of eight models projected carbon tax revenue increases from 2020 through 2040. The carbon tax scenarios with larger annual rate increases resulted in steeper trajectories of increasing revenues through 2040. The models' estimates of annual carbon tax revenue in 2040 ranged from approximately $250 billion to $475 billion (under the tax rate scenario of $50/metric ton, increasing 5% annually). Fossil fuels have a wide range of CO 2 emission intensity (i.e., emissions per unit of energy). As illustrated in Figure 4 , the CO 2 emission intensity of coal is approximately 30% more than oil and approximately 80% more than natural gas. These emissions intensity differences would lead to different tax rates per unit of energy across different fuels in a carbon tax regime. Carbon taxes could affect fuel prices in complex ways. The change in consumer fuel prices would likely not be the same as the price paid by the party directly subject to the tax. Actual price impacts for consumers would depend on multiple factors, including whether: a carbon tax is applied at the beginning of the production process ("upstream") to fossil fuels; and the price impacts are passed through to end users and not absorbed by upstream energy producers or midstream entities, such as retailers. In addition, market participants such as electric power plant operators can avoid paying the increased costs by substituting fuels or technologies. Energy consumers may modify their behavior in the marketplace—energy conservation, consuming less or different products and services—to mitigate impacts from the increased prices. Table 2 includes estimates of price increases on coal, crude oil, natural gas, home heating oil, and motor gasoline based on a carbon tax rate of $25/mtCO 2 that applies CO 2 emissions from fossil fuel combustion. As indicated in the table, a carbon tax would have the greatest impact on the price of coal due to coal's relatively high CO 2 emissions intensity. By comparison, a carbon tax is expected to have less of an impact on the price of gasoline, increasing its price by 8%. Economic models have projected how carbon prices would impact energy use, particularly the consumption of different fossil fuels and less carbon-intensive alternatives, such as renewables or nuclear power. For example, the 2018 EMF 32 study, which included results from 11 modeling groups, assessed how several carbon tax scenarios would impact energy consumption. Highlights of these models' results (compared to reference case scenarios) include the following: Coal consumption could decline by 40% to nearly 100% by 2030 under a $50/mtCO 2 carbon tax, though one model projected an increase in coal due to the model incorporating CCS technology. Natural gas consumption estimates vary across the models, with some showing minimal change in 2030 and others showing declines ranging between 40% and 60%. Oil consumption estimates indicate that the largest decline (approximately 4% by 2030) would occur under the $50/mtCO 2 carbon tax scenario. Wind energy consumption could increase by 48% to 300% by 2030 under a $50/mtCO 2 carbon tax scenario. A carbon tax is one policy option to address U.S. GHG emission levels, which contribute to climate change and related impacts. Economic modeling indicates that a carbon tax would achieve emission reductions, the level of which would depend on which GHG emissions and sources are covered and the rate of the carbon tax. A carbon tax would generate a new revenue stream. The magnitude of the revenues would depend on the scope and rate of the tax and multiple market factors, which introduce uncertainty in the revenue projections. A 2018 CBO study estimated that a $25/metric ton tax on CO 2 emissions from energy-related activities and other selected GHG emission sources would yield approximately $100 billion in the first year of the program. To put this estimate in context, the CBO projected that total federal revenue would be $3.5 trillion in FY2019. Policymakers would face challenging decisions regarding the distribution of the new carbon tax revenues. Depending on the level of the tax, some economic analyses indicate that the distribution of tax revenue could yield greater economic impacts than the direct impacts of the tax. Some models indicate that the economic impacts are greatest in the early years of the carbon tax. Policymakers could apply the tax revenues to support a range of policy objectives. When deciding how to allocate the revenues, policymakers would encounter trade-offs among objectives. The central trade-offs involve minimizing economy-wide costs, lessening the costs borne by specific groups—particularly low-income households—and supporting a range of specific policy objectives. A primary concern with a carbon tax is the potential economy-wide costs that may result. The potential costs would depend on a number of factors, including the magnitude, design, and use of revenues of the carbon tax. In general, economic literature finds that some of the modeled revenue applications would reduce the economy-wide costs imposed by a carbon tax but may not eliminate them entirely. Policymakers and stakeholders may have different perspectives regarding whether these estimated economy-wide costs (typically measured in terms of GDP loss) represent a significant concern. Some argue that the estimated economy-wide costs should be compared with the policy option of not establishing a carbon tax. This comparison is uncertain as carbon tax analyses do not generally consider the benefits that would be gained by reducing GHG emissions and avoiding climate change and its adverse impacts. Some studies cite particular economic modeling scenarios in which a carbon tax and revenue recycling could produce a net increase in GDP or economic welfare, compared to a baseline scenario. These scenarios involve using carbon tax revenues to offset reductions in existing, distortionary taxes, such as corporate income or payroll taxes. Although the models indicate that these revenue applications would yield the greatest benefit to the economy overall, the models also find that lower-income households would likely face a disproportionate impact under such revenue applications. As lower-income households spend a greater proportion of their income on energy needs, these households are expected to experience disproportionate impacts from a carbon tax if revenues were not recycled back to them in some fashion, such as a lump-sum distribution. Carbon tax revenues that are used to offset the burden imposed on various sectors or specific population groups would not be available to support other objectives. An additional concern with a carbon tax involves potential disproportionate impacts to "emission-intensive, trade-exposed industries." Policymakers could select among several options to address these concerns, either by establishing a border carbon adjustment program or allocating some of the carbon tax revenues to selected industry sectors based on an output-based metric. If other nations were to adopt comparable carbon price policies, this concern may be alleviated to some degree. Relatedly, a carbon tax is projected to disproportionately impact fossil fuel industries, particularly coal, and the communities that rely on their employment. To alleviate these impacts, policymakers could allocate some of the carbon tax revenue to provide transition assistance to employees or affected communities. Table A-1 identifies sources of GHG emissions that account for 0.5% or more of total U.S. GHG emissions. The sources are listed in descending order by their percentage contribution. CO 2 emissions from fossil fuel combustion, which accounts for almost 76% of total U.S. GHG emissions, are broken down by fossil fuel type: petroleum, coal, and natural gas. The table identifies potential points in the economy at which a carbon tax could be applied. The table lists the approximate number of entities that would be involved with different tax applications. The number of entities listed is current as of the most recent data available and varies accordingly by category. See table notes for details. The right-hand column of the table provides additional comments for some of the emission sources. In some cases the comments discuss potential opportunities for additional GHG emissions coverage at a particular source. In other cases, the comments address potential limitations of covering all of the emissions from a particular source.

Question: Write a one-page summary of the report 1.

Answer: Names for Navy ships traditionally have been chosen and announced by the Secretary of the Navy, under the direction of the President and in accordance with rules prescribed by Congress. Rules for giving certain types of names to certain types of Navy ships have evolved over time. There have been exceptions to the Navy's ship-naming rules, particularly for the purpose of naming a ship for a person when the rule for that type of ship would have called for it to be named for something else. Some observers have perceived a breakdown in, or corruption of, the rules for naming Navy ships. On July 13, 2012, the Navy submitted to Congress a 73-page report on the Navy's policies and practices for naming ships. For ship types now being procured for the Navy, or recently procured for the Navy, naming rules can be summarized as follows: The first Ohio replacement ballistic missile submarine (SSBN-826) has been named Columbia in honor of the District of Columbia, but the Navy has not stated what the naming rule for these ships will be. Virginia (SSN-774) class attack submarines are being named for states. Aircraft carriers are generally named for past U.S. Presidents. Of the past 14, 10 were named for past U.S. Presidents, and 2 for Members of Congress. Destroyers are being named for deceased members of the Navy, Marine Corps, and Coast Guard, including Secretaries of the Navy. The Navy has not yet announced a naming rule for its planned new class of FFG(X) frigates, the first of which the Navy wants to procure in FY2021. Previous classes of U.S. Navy frigates, like Navy destroyers, were generally named for naval leaders and heroes. Littoral Combat Ships (LCSs) are being named for regionally important U.S. cities and communities. Amphibious assault ships are being named for important battles in which U.S. Marines played a prominent part, and for famous earlier U.S. Navy ships that were not named for battles. San Antonio (LPD-17) class amphibious ships are being named for major U.S. cities and communities, and cities and communities attacked on September 11, 2001. John Lewis (TAO-205) class oilers are being named for people who fought for civil rights and human rights. Expeditionary Fast Transports (EPFs) are being named for small U.S. cities. Expeditionary Transport Docks (ESDs) and Expeditionary Sea Bases (ESBs) are being named for famous names or places of historical significance to U.S. Marines. Navajo (TATS-6) class towing, salvage, and rescue ships are being named for prominent Native Americans or Native American tribes. Since 1974, at least 21 U.S. military ships have been named for persons who were living at the time the name was announced. The most recent instance occurred on May 6, 2019, when the Navy announced that it was naming the destroyer DDG-51 for former Senator Sam Nunn. Members of the public are sometimes interested in having Navy ships named for their own states or cities, for older U.S. Navy ships (particularly those on which they or their relatives served), for battles in which they or their relatives participated, or for people they admire. Congress has long maintained an interest in how Navy ships are named, and has influenced the naming of certain Navy ships. The Navy suggests that congressional offices wishing to express support for proposals to name a Navy ship for a specific person, place, or thing contact the office of the Secretary of the Navy to make their support known. Congress may also pass legislation relating to ship names. Measures passed by Congress in recent years regarding Navy ship names have all been sense-of-the-Congress provisions.