A tall, husky man with a large machine gun stands next to a missile in a field just south of Damascus, Syria. It’s a warm morning in May, and pale yellow butterflies flutter around him. Rabieh is a Hezbollah fighter stationed in the area, and like other Hezbollah members who spoke to Newsweek, he asked to be identified by a pseudonym because he isn’t authorized to speak to the press. "God willing, we will soon liberate Syria and go back to our country,” Rabieh says. "But until that happens, we will stay here until our last breath.”

Since 2012, Hezbollah, the Iran-backed Lebanese Shiite organization, has been fighting alongside Syrian President Bashar al-Assad against rebel and extremist groups. Though many of its fighters have died in these hills and beyond, Hezbollah has emerged stronger and emboldened from the war. The Syrian conflict has given it training and experience, as well as an impressive arsenal of weapons, courtesy of Iran, Assad and Russia.

But that strength could be short-lived. The reason: renewed tension with Israel. The southern Lebanese border has long been precarious territory. But Hezbollah fighters and officials say they have recently shifted troops to the area from Syria, out of concern that their enemy is preparing for a new conflict there. And several times in the past few months, the United States struck Hezbollah targets in Syria, prompting Hassan Nasrallah, the group’s leader, to warn of retaliatory strikes if America continues to infringe upon the territory it holds in the country.

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The renewed tensions come at a time when Hezbollah is also helping Shiite militias fight the Islamic State militant group (ISIS) in Iraq. So if war with Israel breaks out, as it last did in 2006, Lebanon’s “Party of God” could soon be active on three fronts—and risk losing everything it gained from helping Assad. As Hilal Khashan, a politics professor at the American University of Beirut, puts it: “If Israel wants to launch an all-out war, Hezbollah would stand no chance.”

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Aziz Taher/Reuters

Formidable Foe?

The Shiite group doesn’t seem concerned about being overstretched—at least according to two commanders in Dahieh, a suburb of Beirut. On the streets, portraits showing a smiling Nasrallah adorn the walls, along with photos of handsome young fighters posing next to weapons—all men from the neighborhood who died while fighting in Syria. The two commanders sit side by side on a couch, smoking cigarettes and drinking syrupy tea. One is a ranking officer; the other, his lieutenant. “Since we went into Syria, we became much stronger,” the older officer says. “What was Hezbollah before? We were defenders. Now, we’ve learned how to attack offensively.”

The lieutenant interjects. “Hezbollah now has weapons that we never dreamed of,” he says proudly. “When Syria was at peace, we could never have had access to such weaponry, especially at these low prices.”

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During the 2006 war with Israel, the group proved a difficult foe. Unlike the Palestinian militants Israel must contend with in the West Bank and Gaza, Hezbollah had decades of training and sophisticated weapons. Russian-made anti-tank missiles tore at Israeli ground forces, eventually forcing Jerusalem to agree to a cease-fire. The region’s most powerful army lost 120 soldiers, far more than it had in any conflict since the second Palestinian intifada. (Hezbollah’s casualties ranged from 49 to 300, according to estimates.)

The Shiite group is far stronger than it was more than a decade ago. “What the world saw from Hezbollah in 2006 is 3 percent of what we are now,” says Mustafa, a Hezbollah fighter. “Especially after the experience we’ve gained in Syria. A boy who was 18 years old and went to fight in Syria—now, he is 25. He saw his friends die in front of him; he lost family there. He has nothing left to lose. He will fight until the last drop of blood in his body.”

There’s some truth in his bravado. Since the 2006 war, Hezbollah has built up its store of advanced weaponry with help from the Syrian regime and its Iranian sponsors. In 2016, the group commanded an estimated 20,000 active troops and 25,000 reservists, making it comparable to a medium-sized army. “Hezbollah is the most resilient and militarily capable sub-state actor the world has ever known, period,” says Bilal Saab, a fellow at the Atlantic Council, a think tank based in Washington, D.C.

Israel believes Hezbollah has 120,000 rockets ready to be used in the event of a war—an arsenal larger than those of most states in the European Union. The group has also improved its system of underground tunnels in the south—some of which it claims lead into Israeli territory.

“War with Israel…will change the whole Middle East,” the older commander in Dahieh predicts. “Everybody is going to fight. Women and children will pick up knives.… We were keeping our Borkan-1 missiles as a secret weapon to use against the Israelis, but then we had to use them in Syria, and now the Israelis know we have them. Imagine that in one hour, we can fire 4,000 missiles. We can enter Israeli territory on ATVs and weaponized drones and bikes. They have no idea how we can hit their gas infrastructure. We have anti-aircraft missiles. The [Israeli] planes will leave the airport and immediately explode.”

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Some experts dispute his claims. Even if the group weren’t fighting in Syria and Iraq, these analysts say Hezbollah would be considerably outgunned by its enemy to the south. The 2006 war alarmed Israel, which has also built up its arsenal, thanks to arms deals with the U.S., and obtained top-of-the-line missile defense systems such as the Iron Dome. (Israel claims it intercepted 90 percent of the rockets fired at it during the 2014 Gaza War—though experts question that figure.)

“We know very well about all the efforts of Hezbollah,” says Jacques Neriah, a former Israeli military intelligence official. “The first thing that Israel will have to do is try to neutralize [Hezbollah’s] missile threat. This will be done in different ways, and in very ingenious ways, so that Israel would suffer the minimum from rockets coming from Lebanon. We are a stubborn people…. I don't advise Hezbollah to underestimate [us].”

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Gil Cohen Magen/Reuters

Preparing to Fight

Given the damage the two sides could inflict on each other, the status quo—mutual deterrence—could continue. Over the past decade, war seemed imminent between the two sides on several occasions. In January 2015, an Israeli airstrike took out a Hezbollah convoy in Syria. The group retaliated by attacking Israeli troops on the border. But the fighting didn’t escalate, nor did war break out after repeated Israeli strikes on what it says were Hezbollah weapons sites in Syria, most recently on June 25.

The recent increase in military activity by both parties, however, doesn’t bode well for peace. In March, Israel conducted a series of drills on its northern border, using a simulated Lebanese village to train its soldiers to fight in Hezbollah territory. More recently, the Shiite group moved fighters into southern Lebanon to prepare for an invasion, citing intelligence and observation of Israeli troop movements. “The Syrian army can handle the situation now,” says a division leader in Dahieh. “Now, our main focus is in the south.”

The tension on the Lebanese side of the Israeli border is palpable, as it has been for years—but given the Shiite group’s expectations of war and the increased American involvement in Syria, there’s a new note of urgency here. This is Hezbollah’s heartland and the place where the Party of God keeps its missiles in bunkers, hidden throughout the lush valleys and hills. It’s also the place where residents have the most to lose, but they’ve grown accustomed to living with the threat of conflict. “They’re preparing, and we’re preparing,” a Hezbollah official in the south says, referring to the Israelis. “It’s part of our culture to teach our children and children’s children to fight.”

He predicts the war will begin before the summer is over. If he’s right, fighters such as Rabieh—the one in Syria—could be headed to a new front. “Any violation in Lebanon or Syria by the Israelis,” Rabieh says, “we will be there.”

With Jack Moore in London.

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