Hezbollah, Iran’s proxy in Lebanon, has joined the war against the United States and Israel, launching missiles and drones at Israeli military sites in response to the assassination of Iran’s supreme leader and other senior officials. Israel promptly responded by killing Hezbollah’s intelligence chief and bombing Hezbollah positions in Lebanon. On Tuesday, Israel even sent more ground forces into southern Lebanon and warned 80 villages to evacuate.

Israel’s fight against Hezbollah will not be easy. Hezbollah remains deeply embedded in Lebanon, and the dysfunction of the Lebanese army and political system stands in the way of defeating the group. Hezbollah is adapting to war by promoting new leaders to replace those who have fallen and decentralizing its military operations. The group also still has rockets, drones, and missiles to launch and can likely mount overseas terrorist attacks, as it has in the past.

Israel has fought Hezbollah for over 40 years—sometimes with on-again, off-again strikes, and in other cases with massive bombings and limited invasions of Lebanon—and the group, while battered, survived.

But Hezbollah, once described by a senior U.S. official as the “A-team of terrorists,” is no longer what it once was. Since 2023, the group has been devastated by attacks from Israel, and its longtime ally, the Assad regime, has fallen. Its patron, Iran, has been battered by U.S. and Israeli airstrikes, both ongoing and from last June, and by domestic unrest. And Hezbollah’s opponents at home, long cowed by the group’s popular appeal and willingness to kill, are finally standing up. Politically, Hezbollah today may be weaker than at any time since its founding in the 1980s.

In other words, Hezbollah is down but not out. The United States, Israel, and regional partners should seize on Iran’s vulnerability to step up pressure on Hezbollah even further. It is possible to diminish the group’s power and influence permanently, but it will take sustained pressure, long-term investment in state institutions, including the Lebanese Armed Forces, and careful diplomacy.

‘FROM AN ARMY TO A MILITIA’

Hezbollah’s trials began on October 8, 2023, the day after Hamas’s devastating attack on Israel. After decades of on-again, off-again conflict, Hezbollah and Israel exchanged limited tit-for-tat blows for months. In September 2024, however, Israel went on the offensive. It killed or wounded over 1,000 members of Hezbollah by detonating explosives hidden in their pagers and walkie-talkies. Israel followed by striking Hezbollah’s military positions, assassinating high-ranking officials, including the group’s long-time leader Hassan Nasrallah, and invading southern Lebanon. Reeling from these attacks, Hezbollah’s vaunted military forces and arsenal of rockets and missiles proved ineffective. In November 2024, the group agreed to a ceasefire, under which it withdrew its forces from south of the Litani River, which sits about 20 miles........

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