What to Know as Israel and Hezbollah Stand on Brink of New War

For months, concerns have grown that the war in Gaza might ignite a second conflict between Israel and Hezbollah, the well-armed militia that is loosely allied with Hamas and based just across Israel’s northern border with Lebanon.

The two sides have repeatedly traded strikes since the Gaza war began in October, killing civilians and combatants in Lebanon and Israel, with most of the civilian casualties in Lebanon. The hostilities have also forced more than 150,000 people on both sides of the border to leave their homes for temporary shelters. That has put pressure on the Israeli government to make the north of the country safe for residents again by pushing Hezbollah back from the border region.

Here’s a look at Hezbollah as it stands on the brink of a new fight, and why that could still be averted.

What is Hezbollah?

Hezbollah has opposed Israel since the group’s very beginnings. It was founded in the 1980s, after Israel, responding to attacks, invaded and occupied southern Lebanon, intending to root out the Palestine Liberation Organization, which was then based in the country.

But Israel soon ran into a new foe, one whose guerrilla fighters quickly grew effective at bedeviling the far-better-equipped Israeli forces: Hezbollah, a Shiite Muslim popular movement that made driving Israel out of Lebanon a major goal.

By 2000, Israel had withdrawn from Lebanon, making Hezbollah a hero to many Lebanese. It fought Israel again in 2006, launching a military operation into its southern neighbor that led to a fierce counterattack. In that war, Israel rained bombs on southern Lebanon and Beirut, the capital; the fighting killed more than 1,000 Lebanese.

Yet, the Israeli military never managed to overwhelm Hezbollah in 34 days of war, allowing the group and its leader, Hassan Nasrallah, to emerge as stars in an Arab world wearily accustomed to being defeated by Israel.

Hezbollah soon allied with Iran, and they became close partners.

Though the group retains a large and loyal following among Shiite Muslims because of the social services and political power it offers them — as well as the authoritarian tactics it uses to quell any dissent — many Lebanese see the group as an obstacle to progress that keeps threatening to drag the country into an unwanted war.

Hezbollah, considered a terrorist group by the United States and other countries, has evolved from a fighting force into a dominant political one, accruing significant influence in Lebanon’s government.

Today, Lebanon is politically deadlocked, but few major changes can occur without Hezbollah’s approval.

What would a wider war mean for Lebanon?

Lebanon can hardly afford a new conflict with Israel.

The country is reeling from years of an economic crisis that has left countless Lebanese in poverty and a political one that has stripped citizens of many basic services. The strikes at the border have displaced about 100,000 Lebanese civilians, depriving many of their income and their homes, and have cost the country billions of dollars in lost tourism and agricultural revenue, Lebanese officials say.

Lebanon can also count on less international support, with its former colonial power, France, distracted by internal politics, said Emile Hokayem, who specializes in Middle East security at the International Institute for Strategic Studies. Other Arab states and Iran, which pumped money into rebuilding Lebanon after 2006, are less willing or able to help.

“It was already difficult in 2006, when the economic situation and Lebanon’s international position were considerably better,” Mr. Hokayem said. “The country is not in a position to deal with this conflict.”

Even some of Hezbollah’s traditionally loyal Shiite Muslim constituents in southern Lebanon are questioning the price of the current fighting. As a result, analysts say, Mr. Nasrallah knows he has to step carefully. He has said that Hezbollah does not want a broader conflict, while warning that his fighters are prepared for one — and that Israel will face serious consequences if it comes.

“If war is imposed, the resistance will fight without constraints, rules or limits,” Mr. Nasrallah said in a speech two weeks ago.

A Hezbollah-Israel war could also metastasize into a larger regional war that would dwarf the ongoing fighting. Such a conflict could draw in Iran, as well as the United States, which has been working to avert further escalation.

Though jitters have grown with the frequency and deadliness of each side’s strikes, Israel, Hezbollah and Iran do not want a full-fledged war, analysts and U.S. officials say. Yet, the only near-certain way to avoid one, they say, is to end the fighting in Gaza with a cease-fire deal between Israel and Hamas, whose Oct. 7 attack led to the war in the enclave.

How strong is Hezbollah?

Through propaganda videos and calibrated strikes, Hezbollah has repeatedly displayed signs of a bulked-up arsenal that analysts say is capable of inflicting heavy damage on Israeli cities. Its forces are also battle-tested after years of fighting against rebels in Syria, where Hezbollah sent thousands of fighters during that country’s civil war to help prop up the government of President Bashar al-Assad, a close ally of Iran and Hezbollah.

Iran-backed militia fighters in Iraq could also join the fight if Israel attacks Lebanon, said Mr. Hokayem, the Middle East expert.

Estimates vary about just how many missiles Hezbollah has and just how sophisticated its systems are. The Central Intelligence Agency’s World Factbook says the group may have more than 150,000 missiles and rockets of various types and ranges. It also estimates that the group has up to 45,000 fighters, though Mr. Nasrallah has claimed to have 100,000.

But analysts and Israeli officials say Hezbollah’s arsenal is considerably more dangerous than Hamas’s because of its precision-guided missiles, which could target critical Israeli infrastructure and military assets.

Hezbollah has also displayed exploding drones that can elude Israel’s Iron Dome, the detect-and-shoot-down system designed to protect the country from incoming rockets and missiles. The group also appears to have anti-tank missiles that fly too fast and too low for the Iron Dome to intercept.

Mr. Nasrallah warned in his speech two weeks ago that Hezbollah had so far used just a small fraction of its weapons. If necessary, he said, Hezbollah could launch them on “a bank of targets” in precision strikes.

“The enemy knows it must expect us on land, in the air and at sea,” he said.

Some in Israel are wary of exposing their country to such an arsenal. But others argue that Israel must do something before Hezbollah grows stronger.

“The predicament the Israelis find themselves in is that Hezbollah seems to have reached a level of capability at which it’s arguably not worth it for the Israelis to open up a larger conflict,” said Sam Heller, a Beirut-based analyst at Century International.

Euan Ward contributed reporting.