On July 14, a mysterious explosion rocked the southern Lebanese town of Khirbet Silim, destroying a building. United Nations peacekeepers later claimed that the building was a Hezbollah weapons depot that had accidentally blown up. Hezbollah, a Shiite militia with close ties to Iran, has remained silent about the blast's cause, but the group made clear that it does not appreciate the renewed international attention focused on its arsenal.

Under the Security Council resolution that ended the 2006 war between Israel and Hezbollah, blue-helmeted UN troops are responsible for intercepting illegal weapons shipments and shutting down storage sites south of the Litani River. But when UN troops tried to raid another suspected weapons cache in Khirbet Silim a few days after the explosion, hundreds of villagers surrounded the soldiers, pelted them with rocks, and forced them to withdraw. Peacekeepers fired warning shots in the air as they cleared a path out of town. Ever since, black-capped Hezbollah men have stood guard outside the house.

Since the June 7 Lebanese parliamentary elections, an alluring but simplistic narrative has emerged in the West: because Hezbollah and its allies were defeated at the polls, the militant group would lose some of its luster and a pro-American political coalition would rule Lebanon. In fact, Hezbollah remains the country's dominant military and political force. Moreover, it holds the key to both domestic and external stability -- its actions will determine whether there is another war with Israel or if Lebanon will once again be wracked by internal conflict. By losing the election, Hezbollah also avoided being held accountable by Lebanon's other sects -- without power, there is little responsibility.

Under the Saudi-brokered Taif Accord that ended Lebanon's 15-year civil war, all of the country's militias were disarmed. But Hezbollah was allowed to keep its weapons as a "national resistance" against the Israeli occupation of southern Lebanon, which ended in May 2000. When the Israelis withdrew, many Lebanese asked why Hezbollah did not give up its arms and become a strictly political movement. Hezbollah insisted that because Israel was still occupying a tiny strip of land -- called Shebaa Farms -- at the murky intersection of Israel, Lebanon, and Syria, its mission of resistance was not over. The UN later determined the area to be Syrian, not Lebanese, territory.

The last war began after Hezbollah fighters crossed the border and abducted two Israeli soldiers on July 12, 2006. Hezbollah miscalculated, and Israel launched its most intense attack since its 1982 invasion of Lebanon. The offensive crippled the country's infrastructure, displaced one million people, cut Lebanon off from the world, and killed more than 1,000 Lebanese -- the majority of them civilians. Hezbollah, in turn, fired nearly 4,000 rockets at Israel, killing 43 civilians. During 34 days of fighting, 120 Israeli soldiers were killed, many of them by Hezbollah's potent arsenal of antitank rockets. Throughout the war, the Lebanese army remained on the sidelines. Today, it is still as ill-equipped and ill-trained as it was in 2006, and it is unlikely to be involved if another war breaks out. The main difference now is that the army is deployed in southern Lebanon, alongside 13,000 UN peacekeepers.

In recent weeks, Hezbollah officials have ratcheted up their rhetoric, pledging that they are ready for war with Israel and warning against UN attempts to seek out Hezbollah's weapons and rockets. Hezbollah leaders boast that the group now has an even larger and more potent stash of missiles than it did three years ago. Israeli officials -- who are also escalating their war rhetoric -- estimate Hezbollah's arsenal at between 40,000 and 80,000 rockets.

On August 10, Israeli Prime Minister Benjamin Netanyahu warned that his administration would hold the Lebanese government responsible for any attacks on Israeli targets by Hezbollah. "It should be clear that the Lebanese government, as far as we are concerned, is responsible for every attack -- every attack -- launched from its territory against Israel," Netanyahu told Israel Radio. "It cannot hide and say, 'Well, that's Hezbollah, and we don't control them.'"

Some political leaders and analysts in Lebanon interpreted Netanyahu's comments as a signal that Israel would no longer distinguish between the Lebanese state and Hezbollah, especially while the group has a sizable bloc in parliament and seats in the cabinet. Other Israeli officials have suggested that Israel would retaliate against Lebanon if Hezbollah makes good on its promise to avenge the February 2008 assassination of its military commander, Imad Mughniyah, in Damascus -- an act of revenge that Israel worries could take the form of an attack on Israeli tourists, embassies, or other targets outside Israel.

A few days after Netanyahu's comments, Israeli President Shimon Peres tried to calm tensions by once again drawing a distinction between the Lebanese state and Hezbollah. "There was not in the past nor is there now any reason for Lebanon to be Israel's enemy or for Israel to be Lebanon's enemy," Peres said. But Netanyahu's warning is more representative of the Israeli military and political establishment, which both view Hezbollah as a significant danger.

Despite the increasing threats, neither side has an immediate interest in launching a war. Israel is more concerned about Iran than Hezbollah, although if Israel attacks Iran's nuclear facilities, it is likely that the militia would be part of the Iranian retaliation. Aside from an Iranian-Israeli confrontation, Hezbollah is absorbed in internal Lebanese politics and cannot afford to be seen as instigating another war with Israel. The Shiite group's other main backer, Syria, is trying to improve its relations with Saudi Arabia and the United States, and Damascus would likely frown upon renewed conflict in the region. But the danger of heightened rhetoric and a military buildup is that the situation could get out of control.

Not surprisingly, Hezbollah's response to the Israeli threats has been defiant. At a rally in southern Beirut on August 14, marking the third anniversary of the war's end (what Hezbollah calls its "divine victory"), the group's leader, Hassan Nasrallah, laid out his new military strategy. Speaking from an undisclosed location, he warned Israel, "If you launch another war on south Lebanon, imagining that you can bomb any city or village in Lebanon, I will tell you this: today we are capable of shelling any city or town in your usurping entity." Nasrallah, who appeared on giant television screens before a crowd of tens of thousands, also vowed to order missile strikes on Tel Aviv if Israel bombs Hezbollah's base of support: the southern suburbs of Beirut. This is an important shift, because during the 2006 war, Israel largely avoided bombing central Beirut, and Hezbollah refrained from firing missiles on Tel Aviv.

In his speech, Nasrallah advanced the idea that Hezbollah's weapons buildup and overall military capability is a deterrent to Israel -- trying to convince the Lebanese that a stronger Hezbollah will prevent a war. "You might ask, 'Do we have the power to prevent a war?' I will reply, 'Yes, there is a very real possibility that, if we cooperate with one another as Lebanese, we will be able to prevent Israel from launching a war against Lebanon,'" Nasrallah told the crowd, which included members of most Lebanese political factions. "I stress to you that there will be surprises in any new war with Israel, God willing. By saying this to the Israelis, we can deter and prevent them. Let them think a million times before waging a war on Lebanon. Let them look for other ways to confront us, but not war."

This is a dangerous assumption on Nasrallah's part because the Israelis have shown that they are not willing to live indefinitely with a well-armed Hezbollah. Nasrallah's argument is also intended to justify the arms buildup to the Sunnis and Christians of Lebanon -- who, due to the militia's recent takeover of West Beirut, are far more worried today about Hezbollah's weapons than they were in 2006.

In May 2008, Hezbollah ignited the worst internal fighting since the end of Lebanon's civil war. Huddled at home in front of their televisions during the weeklong battle, the Lebanese relived one of their worst memories: masked gunmen demanding people's identity cards. The image of gunmen stopping civilians at checkpoints to sort -- and often murder -- them on the basis of religion is perhaps the most enduring symbol of the country's civil war. In response to Lebanese Prime Minister Fouad Siniora's orders outlawing Hezbollah's underground fiber-optic communication network and dismissing a Hezbollah-affiliated security chief at the Beirut airport, the militia dispatched hundreds of heavily armed fighters into the largely Sunni areas of West Beirut. They quickly routed Sunni militiamen, seized their political offices, and shut down media outlets owned by the Sunni leader Saad Hariri (son of the assassinated former Prime Minister Rafik Hariri). On May 15, Siniora's government rescinded its orders, Hezbollah pulled its fighters off the streets, and leaders of the two factions headed to Qatar to negotiate under the Arab League's auspices. That led to a deal for a national unity government, which remains in place today and forms the basis of the next cabinet.

But three months after the parliamentary elections, the pro-Western coalition that won the vote is floundering in the morass of Lebanon's peculiar sectarian politics. The coalition chose Saad Hariri as its prime minister-designate, but he struggled for months to form a cabinet and finally withdrew in frustration on September 10. Lebanese President Michel Suleiman will now consult with legislators on naming a new prime minister -- although Hariri could be asked once again. This political vacuum gives Hezbollah free rein to continue building up its military and escalating its rhetoric of war. In the absence of a strong central state, Hezbollah will remain the most powerful force in Lebanon -- and its weapons will guarantee its dominance.

You are reading a free article.

Subscribe to Foreign Affairs to get unlimited access.

  • Paywall-free reading of new articles and a century of archives
  • Unlock access to iOS/Android apps to save editions for offline reading
  • Six issues a year in print, online, and audio editions
Subscribe Now
  • MOHAMAD BAZZI is an adjunct senior fellow for Middle East studies at the Council on Foreign Relations and a journalism professor at New York University.
  • More By Mohamad Bazzi