	Background

Since achieving political independence in 1943, Lebanon has struggled to overcome a series of internal and external political and security challenges. Congress and the executive branch historically have sought to support pro-U.S. elements in the country, and in recent years the United States has invested more than $1 billion to develop Lebanon's security forces. Other Members have criticized U.S. policy and sought to condition U.S. assistance to limit its potential to benefit anti-U.S. groups. Congress has appropriated more than $1 billion in assistance ( Table 3 ) for Lebanon since the end of the 34-day Israel-Hezbollah war in 2006 to strengthen Lebanese security forces and promote economic growth. Recent Developments

The war in neighboring Syria, the influx of Syrian refugees, Hezbollah's intervention on behalf of President Asad, Lebanese Sunni support for Syrian opposition forces and a wave of sectarian violence and terrorist attacks by Sunni extremist groups have heightened tensions and complexities surrounding all of these issues. Its leaders argue that extremists will target Lebanon even if Hezbollah withdraws, and its supporters are critical of Lebanese Sunni support for extremism at home and in Syria. Echoing these concerns, the U.S. intelligence community told Congress in its 2014 Worldwide Threat Assessment that, "Lebanon in 2014 probably will continue to experience sectarian violence among Lebanese and terrorist attacks by Sunni extremists and Hezbollah, which are targeting each-others' interests. …Increased frequency and lethality of violence in Lebanon could erupt into sustained and widespread fighting." The Amal movement continued as a political, social, and militia organization and disarmed following the civil war. Hezbollah's ties to Iran and its status as a defender of Lebanese security and priorities have been placed under increased scrutiny in Lebanon because of the group's military intervention in Syria on behalf of the Iran-aligned Asad government. U.S. officials report that Hezbollah has provided assistance and training to Shia militia forces in Syria, and in 2013, it overtly intervened in Syria on behalf of the Asad government. U.S. Assistance and Issues for Congress

Following Syrian withdrawal from Lebanon in 2005 and the war between Israel and Hezbollah in the summer of 2006, the George W. Bush Administration requested and Congress appropriated a significant increase in U.S. assistance to Lebanon. Lebanese leaders and their U.S. interlocutors are acutely focused on the threat that potential power vacuums in executive, legislative, and security force leadership positions may pose to Lebanon's security in 2014. Broader evaluation of the direction of U.S. policy toward Syria is ongoing in both chambers and may include new assessments of U.S. engagement in Lebanon. In the interim, Lebanon is likely to remain an arena for sectarian and geopolitical competition, with political paralysis and insecurity as the result.
Lebanon's small geographic size and population belie the important role it has long played in the security, stability, and economy of the Levant and the broader Middle East. Congress and the executive branch have recognized Lebanon's status as a venue for regional strategic competition and have engaged diplomatically, financially, and at times, militarily to influence events there. For most of its independent existence, Lebanon has been torn by periodic civil conflict and political battles between rival religious sects and ideological groups. External military intervention, occupation, and interference have exacerbated Lebanon's political struggles in recent decades.
Lebanon is an important factor in U.S. calculations regarding regional security, particularly regarding Israel and Iran. Congressional concerns have focused on the prominent role that Hezbollah, an Iran-backed Shia Muslim militia, political party, and U.S.-designated terrorist organization, continues to play in Lebanon and beyond, including its recent armed intervention in Syria. Congress has appropriated more than $1 billion since the end of the brief Israel-Hezbollah war of 2006 to support U.S. policies designed to extend Lebanese security forces' control over the country and promote economic growth.
The civil war in neighboring Syria is progressively destabilizing Lebanon. According to the United Nations High Commissioner for Refugees, more than 1 million predominantly Sunni Syrian refugees have fled to Lebanon, equivalent to close to one-quarter of Lebanon's population. Regional supporters and opponents of Syrian President Bashar al Asad are using Lebanon as a transit point and staging ground in a wider regional conflict. Hezbollah has intervened in Syria in support of Asad, and Sunni extremist groups based in Syria are cooperating with Lebanese and Palestinian Sunni extremists in Lebanon to carry out retaliatory attacks against Hezbollah targets.
The U.S. intelligence community told Congress in its 2014 Worldwide Threat Assessment that, "Lebanon in 2014 probably will continue to experience sectarian violence among Lebanese and terrorist attacks by Sunni extremists and Hezbollah, which are targeting each-others' interests.... Increased frequency and lethality of violence in Lebanon could erupt into sustained and widespread fighting." In January 2014, the U.S. State Department warned against all travel to Lebanon in light of growing terrorist threats.
The question of how best to marginalize Hezbollah and other anti-U.S. Lebanese actors without provoking civil conflict among divided Lebanese sectarian political forces remains the underlying challenge for U.S. policy makers. Ongoing political deadlock and the prospect of executive, legislative, and security force leadership vacuums amplify this challenge.
This report provides an overview of Lebanon and current issues of U.S. interest. It provides background information, analyzes recent developments and key legislative debates, and tracks legislation, U.S. assistance, and recent congressional action. It will be updated to reflect major events or policy changes.
For more information on related issues, see CRS Report RL33487, Armed Conflict in Syria: Overview and U.S. Response, coordinated by [author name scrubbed]; CRS Report R43119, Syria: Overview of the Humanitarian Response, by [author name scrubbed] and [author name scrubbed]; and CRS Report RL33476, Israel: Background and U.S. Relations, by [author name scrubbed].