BEIRUT – Syrian government troops and their allies have steadily positioned themselves in key areas on the flanks of the U.S.-led coalition battle for the Islamic State's self-declared capital of Raqqa.
They are attempting to become an indispensable player in uprooting the extremists from Syria entirely.
That presents a major challenge for the coalition, which so far has shunned any cooperation with President Bashar Assad and has partnered instead with local Kurdish-led forces.
As the U.S. has intensified its fight against IS in Syria, Assad and his trusted allies of Russia and Iran are increasingly asserting themselves. A Syrian military offensive has unfolded on several fronts, coupled with Russian airstrikes and a show of force by Iran, which fired ballistic missiles on an IS stronghold this week and pushed militias that it sponsors deeper into the battlefield.
Damascus and its allies have long argued that they are the essential partner to any international effort in Syria, portraying all opposition forces as terrorist groups.
A close look at the map shows that pro-Assad troops have placed themselves in key locations in the anti-IS battle, while staying close to the U.S.-backed Kurdish forces who lead the ground offensive. The Syrian government forces and their allies have placed themselves south of Raqqa and on the outskirts of Deir el-Zour, the IS militants' last refuge.
While government troops may be far from in control of that area and are unlikely to go after the city of Raqqa, Syria expert Sam Heller of the Century Foundation said the forces "have done enough to insert themselves that they're now a fact on the ground."
The aim is "to ensure that they can't easily be excluded, and that they remain on track to ultimately retake the entirety of the country," Heller said.
The United States, he added, "is dealing with it defensively and reactively. I don't think there's any real sense of what to do, beyond defending U.S. troops and partner forces."
The government push against IS began after a cease-fire deal brokered in May by Russia and Iran that designated four "de-escalation zones" in northern, central and southern Syria.
Having largely succeeded in neutralizing most of his rebel opponents, Assad's forces, with the help of Iranian-sponsored Lebanese and Iraqi militias began an elaborate military campaign. It was a multipronged thrust, choking IS supply and escape routes and encircling coalition forces.
With Russia's backing, they sprang out in the desert of Palmyra, eyeing the town of Sukhna, the last IS stronghold in central Syria. Taking Sukhna would cut the militants' supply line to the border with Iraq.
Almost simultaneously, they advanced south and east of Aleppo all the way to Raqqa province, where the coalition is backing the mostly Kurdish force against IS. The battle for Rasafa, a key town southwest of the city of Raqqa, triggered clashes with the Kurdish forces and led to the downing of a Syrian fighter jet by a U.S. warplane.
For the first time in two years, Syrian troops reached the border with Iraq, establishing a link with Iraqi forces that were advancing on their side, and outflanking U.S. troops and allied rebels in Tanf, near the border with Jordan. Syrian military officers described it as a major achievement that boosts the coordination of border security between Iraq and Syria.
That also increased tensions.
U.S officials said the pro-Syrian troops violated a de-confliction agreement between Washington and Moscow and had "threatened" U.S. fighters and allied rebels.
Subsequent U.S. airstrikes hit a convoy and a base of pro-Assad troops and later carried out another raid in the same area, followed by shooting down a drone believed connected to Iranian-supported forces. The drone had fired near the base where the coalition trains Syrian rebels.
It was a sharp escalation in an area that is essential in operations to secure Iraq's borders and potentially advance toward Deir el-Zour.
The U.S. then deployed a truck-mounted missile system in Syria, showing that the U.S. military intends to protect itself.
Bassam Abu Abdullah, a professor of International Relations at Damascus University, said the advances by pro-Assad troops undermined U.S. plans in the area to sever a land corridor linking the capitals of Syria, Iraq, Iran and Lebanon.
The advances also opened the way for cooperation among Syrian, Iranian-backed fighters and the Iraq Popular Mobilization Units for any moves against Deir el-Zour.
These battles are critical for Syria's future, Abdullah said, noting they will force the U.S. to negotiate with the Assad government.
"We are heading toward a bare-knuckle fight, which is likely to be in favor of the Russia-Iran-Syria axis," he said.
Abdullah argued that the U.S. position is being weakened by splits within the Trump administration over Syria policy.
Unlike in Iraq, where the U.S. is a partner with Iraqi troops to liberate Mosul and other IS bastions, Washington has refused to work with Assad, who is mired in Syria's civil war that is in its seventh year and has killed more than 400,000 people.
Aron Lund, also a fellow at the Century Foundation, said that even though Russia and the U.S. may not be interested in an escalation, it is not a given that they can help their allies in Syria avoid it.
Advances by the Syria-Russia-Iran axis offer the U.S. a way out of a bind over how to handle what follows the retaking of Raqqa.
"This is probably something Washington will end up approving of, if not necessarily colluding in," he said, speaking of the Syrian government's designs on Deir el-Zour.
The alternative would be for the Americans to try to do it themselves, either with the Kurdish-led forces — who are unpopular in the largely Arab tribal areas — or by creating a new force while remaining in the area until it is formed.
"In both cases, it would also be likely to draw various forms of Syrian, Russian, Iranian, Iraqi, and of course jihadi resistance," Lund said.