Along the vast mountain range that marks the Lebanon-Syria border, Hezbollah fighters point out recently captured al-Nusra Front training sites and military positions, and describe how they’ve been able to clear the area of the jihadis. They pick their way over the remnants of the al Qaeda affiliate’s makeshift camp, where clothes, tins of foods, and shell casings are strewn across the ground.

“They were fighters with nothing to lose, so some of them fought fiercely — at some points it was hand-to-hand combat,” said one Hezbollah commander. “But our weapon is our will, our passion, and our conviction.”

For the last two weeks, Hezbollah has been fighting along the Qalamoun mountain range, a 450-square-mile area that straddles both Lebanon and Syria, and overlooks the organization’s heartland in Lebanon’s Bekaa Valley. Their enemies are an assortment of fighters belonging to the Islamic State, al-Nusra Front, and elements from the Free Syrian Army. Hezbollah has touted the ongoing Qalamoun battles as a victory, saying it successfully reopened a clear path from Lebanon into Syria and constrained the threat from Sunni militants posed on Lebanon’s border.

With the battle still unfinished and the sound of explosions continuing to ring in the air, the Hezbollah commander describes how they were able to recapture the territory. “We managed to cleanse the area, which had about 40 positions belonging to the terrorists,” he said. “So far, we have liberated 120 square miles.”

According to another fighter, 80 percent of the recaptured area had been under al-Nusra Front’s control, while Islamic State fighters remain in the northern part of the mountain range, where the battle has yet to come.

But Qalamoun is not Hezbollah’s only ongoing battleground. The organization maintains an active presence in both Syria and Iraq, where it is fighting alongside the Syrian army and pro-regime forces across the country. In Iraq, it is providing training and expertise to the “popular committees,” as well as some of the local militias on the ground such as Asaib Ahl al-Haq and Kataib Hezbollah.

But while Hezbollah has dramatically affected conflicts across the Middle East, these wars have transformed the Lebanese organization as well. The group has grown dramatically from an organization that fought the Israeli occupation to a regional player involved in battles beyond Lebanon’s borders. Now, its leaders describe its struggle as nothing less than a war on terror against foreign-backed extremists and necessary to protect people of all faiths across the region.

“We are killing terrorists, and we are protecting Lebanon and the villages in those areas from the same terrorists who are committing massacres across Iraq and Syria,” Hezbollah MP Nawwaf Moussawi told Foreign Policy, while sitting in his office in the parliament building in downtown Beirut.

Moussawi’s remarks are in line with those of other Hezbollah officials, who describe their intervention in Syria as part of their duty to protect Lebanon against the increasing instability in the region. They argue that they and their allies are the only ones taking the fight against extremists like al-Nusra Front and the Islamic State, who they say makes up the bulk of the opposition. Moussawi, in fact, made the case that President Barack Obama’s administration is actively aiding the groups they are supposed to be fighting against. “It seems the U.S. administration does not really want to confront terrorism, instead it is benefiting from the terrorist organizations in order to pressure its political f

oes,” Moussawi said. “Unfortunately, this double game is only giving terrorism longevity.”

Moussawi pointed to the example of the Iraqi Army, which was trained and armed by the United States — but collapsed in the face of Islamic State offensives over the past year. Following the jihadi group’s capture of the city of Ramadi last month, U.S. Defense Secretary Ashton Carter said that the fall of the provincial capital occurred because “the Iraqi forces just showed no will to fight.”

For Moussawi, this was in stark contrast to the performance of groups that Hezbollah has trained in Iraq. “The groups we are working with, the ones who have gained experience fighting alongside us in Syria, are the ones who are standing up to the terrorists,” he said.

As Hezbollah takes on an ever-greater role across the Middle East, some analysts believe that the group is increasingly stretched thin. Its interventions in Iraq and Syria, they say, have caused a drain on its resources and manpower, and came at a hefty cost in popular support.

“A lot of people questioned the logic behind Hezbollah’s total allegiance to the Assad regime in 2011 and 2012, and rightly so,” said Charles Lister, visiting fellow at the Brookings Doha Center. “The organization went from being perhaps one of the most popular sub-state Arab movements to one viewed as hostile by a majority of the region’s Sunni populations.”

“Hezbollah is undoubtedly stretched manpower-wise, which is why we’ve seen them carefully control and limit the extent of their frontline involvement in the conflict in Syria,” he said. “So far, that limitation appears to be ensuring Hezbollah’s survival, but what happens if the Assad regime comes under more concerted pressure?”

While Hezbollah began with a limited presence in Syria, protecting religious shrines and defending the border areas between Lebanon and Syria, its role has expanded significantly in recent months. While there are no official figures pertaining to the number of Hezbollah casualties incurred in the conflict, sources close to the organization have put the number between 600 and 800 over the last four years.

Yet Moussawi does not seem deterred by the detractors or the body count. He appeared confident about the course of the war in Syria, saying that any talk about President Bashar al-Assad’s fall from power “is behind us now,” and that Hezbollah is “stronger than ever.”

He also appeared unconcerned about the recent string of defeats the Syrian army and Hezbollah have suffered, as Islamist rebels have made gains in the northern province of Idlib, and the Islamic State has captured the central city of Palmyra. “This is not the first time there are losses,” he said. “We lost [areas] before, and then we got them back.”

Moussawi was unwilling to provide figures regarding the group’s size and level of recruitment, but he did say that Hezbollah’s numbers have increased significantly since the 2006 war against Israel. As threats made by the militants increase, he said, the party has increasingly received requests from a cross-section of Lebanese society to help train them. Hezbollah, though a Shiite party backed by Iran, has accordingly been training popular committees made up of different sects along the Lebanese border and has been doing the same inside Syria. “We are in a long-term battle, and we have the endurance to see this through,” he said.

But despite Hezbollah’s war on terror, its alliance with the Syrian government has caused it to lose support among the wider Arab population, unhappy to see the party rallying behind an Arab autocrat. Furthermore, the intense sectarian rhetoric in the region has led to the party’s enemies painting it as a Shiite aggressor against Sunnis.

“Whatever happens in Syria, the majority of Sunni Syrians look at Hezbollah as being complicit in the shedding of their blood,” said Randa Slim, adjunct research fellow at the New America Foundation. “No matter how Syria ends up, they will end up being the loser. That mantle of resistance and legitimacy that they have always claimed and clothed themselves with has now gone, and that’s a big cost for them.”

For Hezbollah, the sectarian rhetoric emanating from its foes simply distracts from the real battle — its war against terrorist groups. As far as it is concerned, any viable alternative to Assad has faded away, as the battles continue to rage.

“The moderate opposition is just an illusion,” Moussawi said. “The choice is either Assad or these terrorist organizations.”