It is not the first time that Israel has decapitated Hezbollah.

In 1992, Israel killed Nasrallah’s predecessor, Abbas al-Musawi. “Israel has assassinated multiple Hamas leaders over recent decades, and on all occasions, these groups have come back — stronger, more radical and posing an even graver threat to Israel,” Barnes-Dacey said.

Nasrallah’s death was the culmination of a multi-week assault that started with an attack on a Syrian weapons facility supplying arms to Hezbollah, and was followed by a sophisticated sabotage operation on Hezbollah pagers and radios that killed or incapacitated scores of commanders and damaged the militia’s ability to communicate.

Subsequent airstrikes took out even more commanders. But other than denouncing the attacks in speeches and statements, Iran has largely stood on the sidelines. Nasrallah’s assassination could be the blow that forces Iran to react.

It is not yet clear how much damage the Israeli attacks have done to Hezbollah’s substantial arsenal of weapons, but if the militia has been significantly incapacitated, Iran may not have many options for retaliation.

Iran certainly has the capabilities to attack Israel itself, as it proved in April when it launched a drone and missile attack. But Israel could also deal a very severe setback to Iran militarily and economically, and that is something the Iranian government does not want, Vaez said. “They know that any attack by Iran would then allow Israel to further expand the war and drag Iran into a direct military confrontation with the United States,” he added.

If Hezbollah still has capabilities that it can deploy, Vaez said, that’s probably the likeliest response. “Iran wants to stay out of this as long as it can.”

Iran is good at playing a long game, said Paul Salem, vice president for international engagement at the Middle East Institute in Washington. Instead of reacting with an immediate barrage against Israel, Iran could instead pull back, quietly help Hezbollah repair the damage to its weapons stores and its leadership, and start rebuilding what’s left.

Loading

Unlike Hamas, Hezbollah is not encircled by Israel. The militia has access to weapons supplies from Iranian allies in Syria and Iraq via the relatively porous Lebanese border.

“Hezbollah will, over time, find new leaders,” Salem said. “Those leaders can be trained and armed and given a new set of tactics and strategy. They have suffered a tremendous loss. But it’s not the end of Hezbollah.”

This article originally appeared in The New York Times.