Strong relations between the United States and Israel have led to bilateral cooperation in many areas. Matters of particular significance include the following: Israel's own capabilities for addressing threats, and its cooperation with the United States. Shared U.S.-Israel concerns about Iran, within the context of the U.S. exit from the 2015 international nuclear agreement, and growing tension involving Iran and Hezbollah at Israel's northern border with Syria and Lebanon. Israeli-Palestinian issues, including those involving Jerusalem, Hamas and the Gaza Strip, funding for Palestinians, and a possible Trump Administration peace plan. Israeli domestic political issues, including probable corruption-related indictments against Prime Minister Binyamin Netanyahu and closely contested elections that are scheduled for April 9, 2019. For background information and analysis on these and other topics, including aid, arms sales, and missile defense cooperation, see CRS Report RL33476, Israel: Background and U.S. Relations , by Jim Zanotti; and CRS Report RL33222, U.S. Foreign Aid to Israel , by Jeremy M. Sharp. Israel relies on a number of strengths to manage potential threats to its security and existence. These strengths include robust military and homeland security capabilities, as well as close cooperation with the United States. Israel maintains conventional military superiority relative to its neighbors and the Palestinians. Shifts in regional order and evolving asymmetric threats during this decade have led Israel to update its efforts to project military strength, deter attack, and defend its population and borders. Israel appears to have reduced some unconventional threats via missile defense systems, reported cyber defense and warfare capabilities, and other heightened security measures. Israel has a robust homeland security system featuring sophisticated early warning practices and thorough border and airport security controls; most of the country's buildings have reinforced rooms or shelters engineered to withstand explosions. Israel also has proposed and partially constructed a national border fence network of steel barricades (accompanied at various points by watch towers, patrol roads, intelligence centers, and military brigades) designed to minimize militant infiltration, illegal immigration, and smuggling from Egypt, Syria, Lebanon, Jordan, and the Gaza Strip. Additionally, Israeli authorities have built a separation barrier in and around parts of the West Bank. Israel is not a party to the Nuclear Nonproliferation Treaty (NPT) and maintains a policy of "nuclear opacity" or amimut . A 2017 report estimated that Israel possesses a nuclear arsenal of around 80-85 warheads. The United States has countenanced Israel's nuclear ambiguity since 1969, when Israeli Prime Minister Golda Meir and U.S. President Richard Nixon reportedly reached an accord whereby both sides agreed never to acknowledge Israel's nuclear arsenal in public. Israel might have nuclear weapons deployable via aircraft, submarine, and ground-based missiles. No other Middle Eastern country is generally thought to possess nuclear weapons. Israeli officials closely consult with U.S. counterparts in an effort to influence U.S. decisionmaking on key regional issues, and U.S. law requires the executive branch to take certain actions to preserve Israel's "qualitative military edge," or QME. Additionally, a 10-year bilateral military aid memorandum of understanding (MOU)—signed in 2016—commits the United States to provide Israel $3.3 billion in Foreign Military Financing and to spend $500 million annually on joint missile defense programs from FY2019 to FY2028, subject to congressional appropriations. Israel's leaders and supporters routinely make the case that Israel's security and the broader stability of the region remain critically important for U.S. interests. They also argue that Israel is a valuable U.S. ally. The United States and Israel do not have a mutual defense treaty or agreement that provides formal U.S. security guarantees. Iran remains of primary concern to Israeli officials largely because of (1) Iran's antipathy toward Israel, (2) Iran's broad regional influence, and (3) the probability that some constraints on Iran's nuclear program could loosen in the future. In recent years, Israel and Arab Gulf states have discreetly cultivated closer relations with one another in efforts to counter Iran. Prime Minister Netanyahu has sought to influence U.S. decisions on the international agreement on Iran's nuclear program (known as the Joint Comprehensive Plan of Action, or JCPOA). He argued against the JCPOA when it was negotiated in 2015—including in a speech to a joint session of Congress—and welcomed President Trump's May 2018 withdrawal of the United States from the JCPOA and accompanying reimposition of U.S. sanctions on Iran's core economic sectors. A few days before President Trump's May announcement, Netanyahu presented information that Israeli intelligence operatives apparently seized in early 2018 from an Iranian archive. He used the information to question Iran's credibility and highlight its potential to parlay existing know-how into nuclear-weapons breakthroughs after the JCPOA expires. In his September 2018 speech before the U.N. General Assembly, Netanyahu claimed that Iran maintains a secret "atomic warehouse for storing massive amounts of equipment and materiel." An unnamed U.S. intelligence official was quoted as saying in response, "so far as anyone knows, there is nothing in [the facility Netanyahu identified] that would allow Iran to break out of the JCPOA any faster than it otherwise could." After Netanyahu publicly exposed the Iranian nuclear archive, some former Israeli officials speculated about what action Israel might consider taking against Iranian nuclear facilities if Iran abrogates the JCPOA and expands nuclear activities currently restricted under the agreement. However, Netanyahu had said in an interview that he was not seeking a military confrontation with Iran. Israel and Iran have engaged in hostile action over Iran's presence in Syria. In the early years of the Syria conflict, Israel primarily employed air strikes to prevent Iranian weapons shipments destined for the Iran-backed group Hezbollah in Lebanon. Later, as the Syrian government regained control of large portions of the country with Iranian backing, Israeli leaders began pledging to prevent Iran from constructing and operating bases or advanced weapons manufacturing facilities in Syria. Since 2018, Israeli and Iranian forces have repeatedly targeted one another in and over Syrian- and Israeli-controlled areas. In January 2019, Prime Minister Netanyahu said that Israel had targeted Iranian and Hezbollah targets in Syria "hundreds of times." Limited Israeli strikes to enforce "redlines" against Iran-backed forces could expand into wider conflict, particularly if there is a miscalculation by one or both sides. U.S. involvement in Syria could be one factor in Israeli calculations on this issue. The U.S. base at Al Tanf in southern Syria has reportedly "served as a bulwark against Iran's efforts to create a land route for weapons from Iran to Lebanon." Israeli officials favor continued U.S. involvement in Syria, while also preparing for the possibility that they may need to take greater direct responsibility for countering Iran there. Russia's advanced air defense systems in Syria could make it more difficult for Israel to operate there. Since 2015, Russia has operated an S-400 system at Russia's Khmeimim air base in Lattakia, a city on Syria's Mediterranean coast. To date, however, Russia does not appear to have acted militarily to thwart Israeli air strikes against Iranian or Syrian targets, and Israel and Russia maintain communications aimed at deconflicting their operations. In addition to the S-400 that it owns and operates, Russia delivered an S-300 air defense system for Syria's military to Khmeimim airbase in October 2018. The delivery followed Syria's downing of a Russian military surveillance plane in September 2018 under disputed circumstances, shortly after an Israeli operation in the vicinity. According to an Israeli satellite imagery analysis company, three launchers appeared to be operational as of February 2019. It is unclear to what extent Russia has transferred the S-300 to Syrian military control, and how this might affect future Israeli military action in Syria. An Israeli journalist wrote that "Israel has the knowledge, experience and equipment to evade the S-300, but the fact that additional batteries, manned by Russian personnel, are on the ground, will necessitate greater care [when carrying out future operations against Iran-aligned targets in Syria]." Since the September 2018 incident, Israeli air strikes appear to have decreased somewhat. On March 25, 2019, President Trump signed a proclamation stating that the United States recognizes the Golan Heights (hereinafter, the Golan) to be part of the State of Israel. The proclamation stated that "any possible future peace agreement in the region must account for Israel's need to protect itself from Syria and other regional threats" —presumably including threats from Iran and the Iran-backed Lebanese group Hezbollah. Israel gained control of the Golan from Syria during the 1967 Arab-Israeli war, and effectively annexed it unilaterally by applying Israeli law to the region in 1981 (see Figure 2 ). President Trump's proclamation changed long-standing U.S. policy on the Golan. Since 1967, successive U.S. Administrations supported the general international stance that the Golan is Syrian territory occupied by Israel, with its final status subject to negotiation. In reaction to the U.S. proclamation, others in the international community have insisted that the Golan's status has not changed. In Congress, Senate and House bills introduced in February 2019 ( S. 567 and H.R. 1372 ) support Israeli sovereignty claims to the Golan, and would treat the Golan as part of Israel in any existing or future law "relating to appropriations or foreign commerce." For decades after 1967, various Israeli leaders, reportedly including Prime Minister Netanyahu as late as 2011, had entered into indirect talks with Syria aimed at returning some portion of the Golan as part of a lasting peace agreement. However, the effect of civil war on Syria and the surrounding region, including an increase in Iran's presence, may have influenced Netanyahu to shift focus from negotiating with Syria on a "land for peace" basis to obtaining international support for Israel's claims of sovereignty. As part of the periodic conflict in Syria between Israel and Iran , some Iranian missiles have targeted Israeli positions in the Golan. The Syrian government has denounced the U.S. policy change as an illegal violation of Syrian sovereignty and territorial integrity, and insisted that Syria is determined to recover the Golan. Additionally, observers have argued that the policy change could unintentionally bolster Syrian President Bashar al Asad within Syria by rallying Syrian nationalistic sentiment in opposition to Israel's claims to the Golan and deflecting attention from Iran's activities inside Syria. Since 1974, the U.N. Disengagement Observer Force (UNDOF) has patrolled an area of the Golan Heights between the regions controlled by Israel and Syria, with about 880 troops from five countries stationed there as of January 2019. During that time, Israel's forces in the Golan have not faced serious military resistance to their continued deployment, despite some security threats and diplomatic challenges. Periodic resolutions by the U.N. General Assembly have criticized Israel's occupation as hindering regional peace and Israel's settlement and de facto annexation of the Golan as illegal. Hezbollah's forces and Israel's military have sporadically clashed near the Lebanese border for decades—with the antagonism at times contained in the border area, and at times escalating into broader conflict. Speculation persists about the potential for wider conflict and its regional implications. Israeli officials have sought to draw attention to Hezbollah's buildup of mostly Iran-supplied weapons—including reported upgrades to the range, precision, and power of its projectiles—and its alleged use of Lebanese civilian areas as strongholds. Ongoing tension between Israel and Iran over Iran's presence in Syria raises questions about the potential for Hezbollah's forces in Lebanon to open another front against Israel. After the September 2018 incident leading to Russia's installation of an S-300 system in Syria (discussed above), Iran reportedly began directly transferring weapons to Hezbollah in Lebanon while reducing Syria's use as a transshipment hub. One Israeli media account warned that Hezbollah's threat to Israel is increasing because of initiatives to build precision-weapons factories in Lebanon and to set up a military infrastructure in southern Syria. In late 2018 and early 2019, Israel's military undertook an effort—dubbed "Operation Northern Shield"—to seal six Hezbollah attack tunnels to prevent them from crossing into Israel. Israeli officials claim that they do not want another war, while at the same time taking measures aimed at constraining and deterring Hezbollah, including through consultation with the U.N. Interim Force in Lebanon (UNIFIL). President Trump has expressed interest in brokering a final-status Israeli-Palestinian agreement, and his Administration has supposedly prepared a proposal to facilitate negotiations, but the Administration has repeatedly postponed releasing the proposal. Many factors may account for the delays, including recent U.S. actions regarding Jerusalem, tension in and around the Gaza Strip, reduced funding for the Palestinians, Israeli settlements in the West Bank, and political jockeying and domestic constraints among Israelis and Palestinians. The U.S. decision—announced in December 2017—to recognize Jerusalem as Israel's capital and move the U.S. embassy there has fed U.S.-Palestinian tensions. Israeli leaders generally celebrated the change, but Palestine Liberation Organization (PLO) Chairman and Palestinian Authority (PA) President Mahmoud Abbas strongly objected. Many other countries opposed President Trump's actions on Jerusalem, as reflected in action at the United Nations. Claiming U.S. bias favoring Israel, Palestinian leaders broke off high-level political contacts with the United States shortly after the December 2017 announcement and have made efforts to advance Palestinian national claims in international fora. However, the PA continues security coordination with Israel in the West Bank. U.S.-Palestinian tensions appear to have influenced Administration decisions to cut off various types of U.S. funding to the Palestinians, and arguably have dimmed prospects for restarting Israeli-Palestinian talks. In a September 2018 address before the U.N. General Assembly, PLO Chairman/PA President Abbas denounced Administration actions that he characterized as taking disputed Israeli-Palestinian issues—such as Jerusalem's status and Palestinian refugee claims—off the negotiating table. Funding for economic and humanitarian needs in the West Bank and Gaza could become even scarcer. In February 2019, Israel announced that it would withhold a portion of the tax revenue it collects for the PA because—pursuant to a law passed by the Knesset in 2018—Israel had determined that amount represented PLO/PA payments made on behalf of individuals allegedly involved in terrorist acts. In response, Abbas announced that the PA would completely reject monthly revenue transfers from Israel if it withheld any amount, even though the transfers comprise approximately 65% of the PA budget. For February, Israel withheld approximately $11 million from the $193 million due to the PA, with the PA rejecting the entire amount as a result. The PA is reportedly seeking temporary financial support from the private sector and local banks, and also asking the Arab League to follow through on its 2010 decision to provide $100 million per month as a "financial safety net" for the PA. At the end of January 2019, U.S. bilateral aid to the Palestinians—including nonlethal security assistance that Israel generally supports—ended completely due to the Anti-Terrorism Clarification Act (ATCA, P.L. 115-253 ), which became law on October 3, 2018. Two months after the law's enactment, PA Prime Minister Rami Hamdallah informed Secretary of State Michael Pompeo that the PA would not accept aid that subjected it to federal court jurisdiction. Apparently, U.S. aid will not resume unless Congress amends or repeals the ATCA, or the Administration channels the aid differently. Assistant to the President and Senior Advisor Jared Kushner has stated that the Administration will publicly release a peace plan sometime after Israeli national elections, which are set to occur on April 9, 2019. According to Kushner, the peace plan contains detailed proposals on the various issues that divide Israel and the PLO. Many observers express skepticism about the prospect that these proposals can serve as a basis for the serious resumption of bilateral talks, but Kushner has reportedly said that the Administration is focusing on formulating "realistic solutions," and that "privately, people are more flexible." U.S. officials hope to surmount potential obstacles to the peace plan in the Israeli and Palestinian domestic arenas by obtaining political and economic support for the U.S. initiative from key Arab states in the region, including Saudi Arabia, the United Arab Emirates, Jordan, and Egypt. A number of Arab states share common interests in working behind the scenes with Israel to counter Iranian regional influence. While some diplomatic developments have fed speculation about warming Arab-Israeli ties, reports suggest that key Arab Gulf states remain reluctant to embrace more formal relations with Israel without a resolution of the Palestinian issue. Saudi Arabia's press agency responded to the U.S. recognition of Israel's claims to sovereignty in the Golan Heights by saying that it "will have significant negative effects on the peace process in the Middle East and the security and stability of the region." In a statement with implications both for domestic and international audiences, Prime Minister Netanyahu reportedly said that the March 2019 change in U.S. policy on the Golan proves that countries can retain territory captured in a defensive war. His statement prompted speculation over the possibility that Israeli leaders might consider annexing part of the West Bank and whether the situation in the Golan is sufficiently similar to invite comparison. Days before the April elections, Netanyahu asserted that if he were to lead the next government, he would apply Israeli law to West Bank settlements. The closely contested Israeli national elections—scheduled for April 9, 2019—and the subsequent government formation process will have significant implications for the country's leadership and future policies. Prime Minister Netanyahu faces a challenge from the centrist Blue and White party under the combined leadership of former top general Benny Gantz and former Finance Minister Yair Lapid. Some setbacks for Netanyahu during the campaign have included the attorney general's announcement of probable corruption-related indictments against Netanyahu, new media allegations of possible misconduct relating to Israel's procurement of German submarines, and questions about some individuals or groups possibly spreading rumors against Netanyahu's opponents via social media. Yet, some observers calculate that Netanyahu's Likud could possibly get fewer Knesset seats than Blue and White and still form the next coalition. For more information on the actors involved in the elections, see CRS Insight IN11068, Israel: April 2019 Elections and Probable Indictments Against Prime Minister Netanyahu , by Jim Zanotti and this report's Appendix . In July 2018, the Knesset passed a Basic Law defining Israel as the national homeland of the Jewish people. Some observers have expressed concern that the law might further undermine the place of Arabs in Israeli society, while others view its effect as mainly symbolic. In March 2019, Netanyahu said that Israel is a Jewish, democratic state with equal rights for all its citizens, and "the nation-state not of all its citizens, but only of the Jewish people," reviving domestic debate about the 2018 law and perhaps seeking support during the election campaign from sympathetic voter groups.

Summary: Strong relations between the United States and Israel have led to bilateral cooperation in many areas. Matters of particular significance to U.S.-Israel relations include Israel's ability to address the threats it faces in its region. Shared U.S.-Israel concerns about Iran and its allies on the nuclear issue and in Syria and Lebanon. Israeli-Palestinian issues. Israeli domestic political issues, including elections scheduled for 2019. Israel relies on a number of strengths to manage potential threats to its security and existence. It maintains conventional military superiority relative to neighboring states and the Palestinians. It also takes measures to deter attack and defend its population and borders from evolving asymmetric threats such as rockets and missiles, cross-border tunneling, drones, and cyberattacks. Additionally, Israel has an undeclared but presumed nuclear weapons capability. Against a backdrop of strong bilateral cooperation, Israel's leaders and supporters routinely make the case that Israel's security and the broader stability of the region remain critically important for U.S. interests. A 10-year bilateral military aid memorandum of understanding (MOU)—signed in 2016—commits the United States to provide Israel $3.3 billion in Foreign Military Financing annually from FY2019 to FY2028, along with additional amounts from Defense Department accounts for missile defense. All of these amounts remain subject to congressional appropriations. Israeli officials seek to counter Iranian regional influence and prevent Iran from acquiring nuclear weapons. Prime Minister Binyamin Netanyahu released new Israeli intelligence on Iran's nuclear program in April 2018, days before President Trump announced the U.S. withdrawal from the 2015 international agreement that constrains Iran's nuclear activities. It is unclear whether Israel might take future military action in Iran if Iranian nuclear activities resume. Since 2018, Israel has conducted a number of military operations in Syria against Iran and its allies, including Lebanese Hezbollah. Israel and Iran also appear to be competing for military advantage over each other at the Israel-Lebanon border. Amid uncertainty in the area, in March 2019 President Trump recognized Israel's claim to sovereignty over the Golan Heights, changing long-standing U.S. policy that held—in line with U.N. Security Council Resolution 497 from 1981—the Golan was occupied Syrian territory whose final status was subject to Israel-Syria negotiation. The prospects for an Israeli-Palestinian peace process are complicated by many factors. Palestinian leaders cut off high-level political contacts with the Trump Administration after it recognized Jerusalem as Israel's capital in December 2017. U.S.-Palestinian tensions have since worsened amid U.S. cutoffs of funding to the Palestinians and diplomatic moves—including the May 2018 opening of the U.S. embassy to Israel in Jerusalem. Palestinian leaders interpreted these actions as prejudicing their claims to a capital in Jerusalem and to a just resolution of Palestinian refugee claims. Israeli Prime Minister Netanyahu has welcomed these U.S. actions. The Trump Administration has suggested that it will release a proposed peace plan after Israeli elections, which are scheduled for April 9, 2019. Speculation continues about how warming ties between Israel and Arab Gulf states may affect Israeli-Palestinian diplomacy, though Saudi Arabia said that the U.S. policy change on the Golan Heights would negatively affect the peace process. Bouts of tension and violence between Israel and Hamas in Gaza have continued—reportedly accompanied by indirect talks between the two parties that are being brokered by Egypt and aim for a long-term cease-fire. Domestically, Israel is preparing for the April 9 elections, which are closely contested. Former top general Benny Gantz is combining with former Finance Minister Yair Lapid to challenge Netanyahu, whom the attorney general has recommended be indicted for corruption in three separate cases. The elections and subsequent government formation process will have significant implications for Israel's future leadership and policies.