Al Qaeda’s leader in Syria reemerged online Sunday with his first official statement in eight months. In the wake of ongoing U.S.-led airstrikes, his threats to attack Western civilians in retaliation for American attacks in Syria were ominous but predictable. Aside from threatening the West, the message was clearly aimed at gaining support from Syrian rebel groups—the same groups U.S. officials have courted as the future ground force to fight ISIS. Essentially, America is competing with al Qaeda for the support of those rebel groups. And so far the momentum is on Qaeda’s side.

Members of the Syrian opposition who had been eyed by U.S. officials as members of a potential proxy force have already condemned the bombardment by America and its allies. Sunday’s statement from Abu Mohammad al-Jolani, the head of Syrian al Qaeda affiliate al-Nusra Front, addressed the rebel groups directly saying that he was their true ally, not the U.S.

In the fractured allegiances and conflicts created by Syria’s brutal civil war, many rebel groups opposed to both ISIS and the Assad regime consider al-Nusra something of a moderate force—despite its loyalty to al Qaeda. To these rebel factions, al-Nusra’s jihadist ideology is secondary to its fight against the Syrian government. In his message Jolani appealed to the idea that al-Nusra is the opposition’s natural leader, imploring rebel groups, “Don’t let the crimes of ISIS [and] its aggression push you towards the West.”

Hassan Hassan, an analyst at the Delma institute in Abu Dhabi whose Twitter feed provided a translation of key points from Jolani’s speech, said it was “tapping into the growing cynicism towards the airstrikes” among Syrians.

The Obama administration has insisted that it will not deploy American troops to Syria. But at the same time, top military and civilian officials have insisted that defeating ISIS requires a ground force that can capitalize on airstrikes and capture territory. That’s left the moderate Syrian rebels, those groups that have fought both the Assad regime and ISIS.

There’s a problem with these moderates, though. This faction of the opposition is itself fractured into dozens of splinter groups. Many government officials and outside observers of the conflict have questioned how the U.S. can be sure which groups are truly moderate and which groups might use U.S. arms in pursuit of a more radical agenda.

The alliance between America and rebel forces has been strained by the U.S. refusal to directly attack the Assad regime. In some ways, the U.S. and its chosen proxies are fighting different wars, despite sharing a common enemy in ISIS. The rebels consider the Assad regime, which has slaughtered tens of thousands of Syrians over years of brutal attacks, their primary enemy, while the U.S. has condemned Assad but focused its attacks only on ISIS and al Qaeda.

That tension led to a symbolic break last week when Harakat Hazm, one of the few vetted rebel groups to receive American weapons and training, called the U.S.-led airstrikes “an attack on national sovereignty” that would only strengthen the Assad regime.

Jolani played the same notes in his statement, stressing the “the possibility of Assad benefiting from the airstrikes,” according to Hassan. But the speech also emphasized the difference between ISIS and al-Nusra. Though they were once aligned, al Qaeda’s leadership excommunicated ISIS in February over the group’s attempt to control the Syrian jihad and its brutality toward fellow Muslims, which was judged to hurt popular support.

This was also stressed in Jolani’s statement, which Hassan said “affirmed his position on ISIS,” which is still unpopular among most Syrians, and reiterated his message that Jabhat al-Nusra will not be like them.” Will a combination of fighting Assad and not being like ISIS be enough for al-Nusra to attract rebel groups disillusioned by the current U.S. strategy? Both houses of Congress approved the President’s plan to arm and train Syrian rebels, but that process will take more than a year to complete. In the meantime, the al Qaeda branch is fighting on the ground and taking on the regime, right now.

Many U.S. officials have already publicly expressed how skeptical they are of the approach in Syria. “We simply don’t know if somewhere down the line it will turn our guns back against us," Rep. Loretta Sanchez, a Democrat from California, said during a congressional hearing this month, questioning the loyalties of rebel groups. Rep. Marlin Stutzman, a Republican from Indiana, similarly expressed “deep reservations about providing funds or arms to Syrian rebels we know little about.” Even supporters of arming the rebels, like Senator John McCain, have questioned whether enough are being trained soon enough to make a difference in Syria’s war. With some rebel groups condemning the U.S. airstrikes—and with al Qaeda making a public play for their loyalties—that skepticism is likely to grow.

Inside the Syrian civil war, al-Nusra can position itself as a necessary ally for groups squeezed between ISIS and the Assad regime. Of course, none of that calculated moderation has made it into the group’s rhetoric toward the West. To American and European civilians, Jolani warns in his statement, “your leaders will not pay the price for the war alone, you will pay the higher price.” Unless the airstrikes in Syria stop and America pulls out of the Middle East, al Qaeda “will transfer the battle to your very homes.” If the West will abide by his demands, Jolani offers this faint incentive: “I think jihadists won’t attack you.”

It’s a message unlikely to deter either the American people or political leaders. But as al-Nusra attempts to co-opt rebel groups and make them seem like impossible allies, it’s contributing to what may be a far more profound shift in U.S. policy than anything boilerplate threats could accomplish.

Sunday night, John Boehner, Republican speaker of the House of Representatives, said the U.S. may have “no choice” other than sending American troops to Syria. On ABC News, Boehner questioned the President’s approach to defeating ISIS. “I don’t believe the strategy he outlines will accomplish it. At the end of the day I think it’s going to take more than airstrikes to drive them out—at some point somebody’s boots have to be on the ground, that’s the point.”