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Israel Kills Leader of Lebanese Hezbollah

September 30, 2024

On September 27, 2024, an Israeli airstrike in Beirut killed Hassan Nasrallah, the longtime Secretary- General of Lebanese Hezbollah. Secretary of Defense Lloyd Austin said that the United States was not involved and had no advance warning. Nasrallah’s killing comes after a series of other Israeli operations against Hezbollah and raises questions about the group’s future capabilities and strategic calculations, along with those of Israel, Iran, and the United States. Hezbollah is a U.S.-designated Foreign Terrorist Organization, a longtime adversary of Israel, and arguably the most powerful of the armed groups Iran backs across the Middle East. The latest round of Hezbollah-Israel fighting has been ongoing since October 2023, when Hezbollah began launching projectiles into northern Israel in stated solidarity with Hamas (another FTO and Iran-backed group). Related issues for Members of Congress include U.S. assistance to Israel and to Lebanon’s armed forces; the deployment of U.S. military forces to the region; and the protection of U.S. citizens, whom the State Department has urged to depart Lebanon.

Israel-Hezbollah Conflict: Background and Escalation

Hezbollah was founded in the 1980s to resist the Israeli invasion of Lebanon during the Lebanese civil war. After Israeli forces’ 2000 withdrawal from Lebanon, Hezbollah has at times engaged in attacks against Israel, including a 34-day war in 2006 that left some 160 Israelis and 1,200 Lebanese dead. The day after the October 7, 2023, Hamas-led attack on Israel, Hezbollah began cross-border rocket attacks. In the following weeks, Israel evacuated roughly 60,000 people from northern Israel, at least partly due to concerns of an October 7-style attack there. They have remained displaced amid escalating violence.

On September 16, 2024, the Israeli government “updated the objectives of the war to include … Returning the residents of the north securely to their homes.” Operations claimed by or attributed to Israeli forces since then include:

• The explosion of hundreds of electronic devices apparently used by Hezbollah members on September 17-18, killing dozens and wounding thousands (including some civilians), while injuring the Iranian ambassador to Lebanon.

• A September 20 airstrike in Beirut that killed Ibrahim Aqil, a commander of the group’s elite Radwan Force, and other senior leaders.

• Israeli airstrikes on hundreds of missiles, launchers, and other targets across Lebanon on September 23, which reportedly killed over 500 Lebanese, including many civilians.

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These and other attacks have reportedly displaced as many as one million Lebanese.

On September 27, Israeli airstrikes in Beirut reportedly targeted Hezbollah’s headquarters and killed Nasrallah and other senior leaders, as well as an Iranian Islamic Revolutionary Guards Corps general. Hezbollah confirmed Nasrallah’s death the following day.

Potential Implications

In the 32 years that Nasrallah led Hezbollah, the Lebanese Shia Muslim group acquired military and political power while supporting Iranian priorities throughout the Middle East, making Nasrallah one of the most prominent leaders in the region. Nasrallah’s killing and the ongoing conflict may affect several actors’ calculations in the Middle East:

• Hezbollah may be in the most precarious position in its history. The group has reportedly lost hundreds of fighters and most of its senior leaders over the past year in Israeli operations, and may have been infiltrated by Israeli intelligence. Any Hezbollah retaliation may be constrained by these organizational and logistical challenges (including the reported loss of 20-25% of its missile arsenal). In addition to declaring its readiness to counter an Israeli ground invasion, Hezbollah may retain some residual capacity to threaten strategic sites or population centers in Israel with missiles and drones. As of September 30, Hezbollah had not announced who will succeed Nasrallah, with possible successors including the group’s temporary acting leader Naim Qassem and senior figure (and Nasrallah’s cousin) Hashem Safieddine. Hezbollah leaders have not signaled any change to Nasrallah’s insistence that Israel end fighting in Gaza before Hezbollah halts its fire against Israel.

• Israel may have accepted risks associated with seeking to degrade Hezbollah’s command structure, military capabilities, and will to fight—possibly deeming these risks preferable to a status quo that left Israeli evacuees displaced and Hezbollah expanding its arsenal. Israeli officials indicate military operations, including ground incursions into Lebanon, may continue until an outcome—diplomatic or otherwise—returns Israeli evacuees to their homes. Some Israeli cross-border raids may have taken place as of September 30, though U.S. opposition to a large ground invasion may possibly help keep these operations relatively small in scope and temporary.

• Iran pledged that Hezbollah would continue to lead Iran-backed resistance efforts, and said Iran would react to Nasrallah’s killing in a time and manner it chooses. Previously, Iran promised to directly retaliate for the July 2024 killing (attributed to Israel) of Hamas leader Ismail Haniyeh in Tehran, but has not done so to date. Iranian leaders may face a challenge in how to support partners against Israel and other adversaries without initiating a broader war that could involve the United States and prove destabilizing to the regime. A weakening of Hezbollah, long considered to be Iran’s closest and most powerful partner force, could affect Iranian leaders’ calculations regarding efforts to increase deterrence by making changes to the country’s nuclear program and support for other regional allies, such as those in Iraq and Yemen that have targeted Israel in response to Israel-Hezbollah escalation.

• The United States may welcome Hezbollah’s setbacks, though heightened Hezbollah- Israel conflict may run counter to the Biden Administration’s apparent preference for lowering regional risks for all actors, including U.S. forces. In a statement after Nasrallah’s death, President Biden called it “a measure of justice,” and pledged continued support for “Israel’s right to defend itself against Hezbollah, Hamas, the Houthis, and any

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• other Iranian-supported terrorist groups.” He also ordered an enhanced U.S. military posture in the region to reduce the risk of broader war, and advocated diplomatic de- escalation in Gaza and Lebanon.

• In Lebanon, a stalemate between Hezbollah, its political partners, and their rivals has blocked the election of a new president since 2022, leaving the country without a fully empowered government for over two years. It is unclear how Nasrallah’s death might affect Lebanese politics or power dynamics involving Lebanon’s army and other actors.

Author Information

Clayton Thomas Specialist in Middle Eastern Affairs

^{Jim Zanotti}

Specialist in Middle Eastern Affairs

Disclaimer

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