This CRS Report discusses U.S. security assistance for Taiwan, formally called the Republic of China (ROC), particularly policy issues for Congress. It also lists sales of major defense articles and services to Taiwan, as approved by the President and notified to Congress since 1990. This report uses a variety of unclassified consultations and citations in the United States and Taiwan. Congress passed and exercises oversight of the Taiwan Relations Act (TRA), P.L. 96-8 , the law that has governed U.S. arms sales to Taiwan since 1979, when the United States recognized the People's Republic of China (PRC) instead of the ROC. The TRA specifies that it is U.S. policy, among the stipulations: to consider any nonpeaceful means to determine Taiwan's future "a threat" to the peace and security of the Western Pacific and of "grave concern" to the United States; "to provide Taiwan with arms of a defensive character"; and "to maintain the capacity of the United States to resist any resort to force or other forms of coercion" jeopardizing the security, or social or economic system of Taiwan's people. Section 3(a) states that "the United States will make available to Taiwan such defense articles and defense services in such quantity as may be necessary to enable Taiwan to maintain a sufficient self-defense capability." The TRA specifies a congressional role in decision-making on security assistance for Taiwan. Section 3(b) stipulates that the President and Congress shall determine the nature and quantity of such defense articles and services "based solely" upon their judgment of the needs of Taiwan, in accordance with procedures established by law. Section 3(b) also says that "such determination of Taiwan's defense needs shall include review by United States military authorities in connection with recommendations to the President and the Congress." In a crisis, Section 3(c) of the TRA requires the President to inform Congress "promptly" of any threat to "the security or the social or economic system" of the people on Taiwan and any danger to U.S. interests. The TRA set up the American Institute in Taiwan (AIT), which continued the functions of the embassy in Taipei. AIT implements policy as directed by the Departments of Defense and State, and the National Security Council (NSC) of the White House. They have controlled notifications to Congress of pending major arms sales, as required by the Arms Export Control Act (AECA), P.L. 90-629. Congress also oversees the President's implementation of policies decided in 1982. President Ronald Reagan agreed with the PRC on the August 17, 1982, Joint Communique on reducing arms sales to Taiwan, but he also clarified that arms sales would continue in accordance with the TRA and with the full expectation of a peaceful resolution of the Taiwan question. At the same time, Reagan extended "Six Assurances" to Taipei, including assurances that Washington had not agreed to set a date for ending arms sales to Taiwan nor to consult with Beijing on arms sales. (On policy for a peaceful resolution, see CRS Report RL30341, China/Taiwan: Evolution of the "One China" Policy—Key Statements from Washington, Beijing, and Taipei , by [author name scrubbed].) U.S. arms transfers to Taiwan have been significant despite the absence of a defense treaty or a diplomatic relationship. Taiwan has ranked among the top recipients of U.S. arms sales. The value of deliveries of U.S. defense articles and services to Taiwan totaled $4.3 billion in the 2004-2007 period and $2.9 billion in 2008-2011. Among customers worldwide, Taiwan ranked fourth (behind Israel, Egypt, and Saudi Arabia) in 2004-2007 and fifth (behind Saudi Arabia, Egypt, Israel, and Australia) in 2008-2011. In 2011, Taiwan ranked eighth among worldwide recipients, receiving $800 million worth of U.S. defense articles and services. As for agreements in 2011 alone, Taiwan ranked sixth among customers worldwide, with agreements worth $1.6 billion. Aggregate values for U.S. arms agreements with and deliveries to Taiwan are summarized below. In addition to transfers of hardware, beginning after the crisis in the Taiwan Strait in 1995-1996 during which President Clinton deployed two aircraft carrier battle groups near Taiwan in March 1996, the Pentagon quietly expanded the sensitive military relationship with Taiwan to levels unprecedented since 1979. The broader exchanges have increased attention to "software," including discussions over strategy, training, logistics, command and control, etc. Also, Taiwan's F-16 fighter pilots have trained at Luke Air Force Base, AZ, since 1997. However, in 2004, Taiwan's Minister of Defense Lee Jye surprisingly wanted to withdraw the pilots and fighters. In response, the Defense Department stressed the value of continuing the training program to develop "mission ready and experienced pilots" with improved tactical proficiency shown by graduated pilots who have "performed brilliantly," as explicitly notified to Congress. In July 2001, after U.S. and Taiwan media reported on the "Monterey Talks," a U.S.-Taiwan meeting on national security that was launched in Monterey, CA, the Pentagon revealed it was the seventh meeting (since 1997) held with Taiwan's national security officials "to discuss issues of interaction and means by which to provide for the defense of Taiwan." Another round of such strategic talks took place in July 2002. The 11 th round of the talks took place in late September 2005, after the Bush Administration postponed the meeting by a couple of weeks to accommodate PRC ruler Hu Jintao's scheduled visit to Washington on September 7 (which was then postponed because of President Bush's response to Hurricane Katrina). These talks have continued. Increased U.S. concerns about Taiwan's self-defense capability prompted expanded communication on defense and security matters. At a conference on Taiwan's defense in March 2002, Deputy Secretary of Defense Paul Wolfowitz said that the United States wanted to help Taiwan's military to strengthen civilian control, enhance jointness, and rationalize arms acquisitions. At a congressional hearing in April 2004, Assistant Secretary of Defense for International Security Affairs Peter Rodman testified that the Pentagon believed Taiwan's military needed to improve readiness, planning, and interoperability among its services. The Pentagon has assessed Taiwan's defense needs, starting with over a dozen studies from 1997 to early 2004. Congress could inquire about such assessments and require reports or briefings. In response to the National Defense Authorization Act (NDAA) for FY1999, P.L. 105-261 , the Defense Department submitted the classified and unclassified reports, respectively in February and May 1999, on theater missile defense options for Taiwan (along with U.S. allies, Japan and South Korea). In September 1999, to enhance cooperation, a Pentagon team reportedly visited Taiwan to assess its air defense capability. The Pentagon reportedly completed its classified assessment in January 2000, finding a number of problems in the Taiwan military's ability to defend against aircraft, ballistic missiles, and cruise missiles, and those problems included international isolation, inadequate security, and sharp inter-service rivalries. In September 2000, the Pentagon reportedly conducted a classified assessment of Taiwan's naval defense needs—as the Clinton Administration had promised in April 2000 while deferring a sale of Aegis-equipped destroyers. The report, "Taiwan Naval Modernization," was said to have found that Taiwan's navy needed the Aegis radar system, Kidd-class destroyers, submarines, an anti-submarine underwater sonar array, and P-3 anti-submarine aircraft. On December 18, 2000, the Defense Department issued a "Report to Congress on Implementation of the TRA," in response to the reporting requirement in the Consolidated Appropriations Act for FY2000 ( P.L. 106-113 ). In January 2001, a Pentagon team reportedly examined Taiwan's command and control, air force equipment, and air defense against a first strike. In September 2001, a Defense Department team reportedly visited Taiwan to assess its army, as the Bush Administration promised in the April 2001 round of arms sales talks. In August 2002, a U.S. military team studied Taiwan's Po Sheng command and control program. In November 2002, another U.S. team visited Taiwan to assess its Marine Corps and security at ports and harbors, and reported positive findings. In November 2003, a U.S. defense team rated Taiwan's anti-submarine warfare (ASW) capability as poor. In 2007-2009, Taiwan's Defense Ministry conducted a Joint Defense Capabilities Assessment (JDCA) with U.S. assistance, to determine requirements for Taiwan's joint defense. In 2010, the Defense Department began more detailed studies of Taiwan's joint defense transformation. In 2009, Congress directed the Defense Secretary to assess Taiwan's air defense forces, including its F-16 fighters, with an unclassified report due by January 26, 2010. As directed by the conference report for the NDAA for FY2010 ( P.L. 111-84 ), on February 16, 2010, the Defense Department submitted an unclassified assessment to Congress, concluding that the PLA's ballistic and cruise missiles as well as fighters have diminished Taiwan's ability to deny the PLA air superiority in a conflict. The study found that although Taiwan had almost 400 combat aircraft, far fewer were operationally capable. Taiwan's F-5 fighters already reached the end of their operational service life. Taiwan's Indigenous Defense Fighters (IDFs) lacked the capability for sustained sorties. Taiwan's Mirage-2000 fighters (from France) were technologically advanced but required frequent, expensive maintenance that reduced their readiness rate. The assessment noted that Taiwan recognized its need for sustainable replacements for obsolete and problematic aircraft.