One year ago the US bombed Syrian Army positions in Deir Ezzor as ISIS advanced. Will there be a repeat as both sides vie for post-ISIS territory?

The Syrian Army continues to make rapid gains against ISIS in the eastern city of Deir Ezzor since breaking the years long terrorist siege earlier this week which had 100,000+ Syrian civilians trapped. On Saturday the army reached its most important goal in the campaign to date - the liberation of Deir Ezzor military airport which had been completely surrounded by ISIS for nearly a year. The army's full control of the airport means that most of Deir Ezzor's western half is now under the control of the government as all regime neighborhoods are now linked up for the first time with ISIS lines cut.

The Syrian foreign ministry said the liberation of the military airport "foreshadowed the end of terrorism". Indeed control of the base has long been considered key to the city's fate. ISIS fighters reportedly began fleeing areas surrounding the base once the army got the momentum, especially as areas adjacent to the base are open fields with little natural cover. The turning point came after the army captured the strategic hilltop of Tal Rubiyat, which overlooks the Ta'meen Base located northwest of the sprawling airport.

Celebrations ensued among Syrian officers and troops the moment Deir Ezzor's most important strategic section was liberated from ISIS on Saturday.

For much of the past year the airport was besieged while over 5000 civilians along with Syrian army and Hezbollah fighters were trapped inside the base. According to various reports from correspondents on the ground, it was defended from near daily ISIS attacks by starving base residents, and supplied from government air drops. Many lost their lives just attempting to access some of the hard to reach airdrops on which the base's survival depended.

The weekend victory means we could see the entire liberation of Deir Ezzor City wrap up more quickly than anyone expected. As the military airport is now able to ramp up operations and become the army's most well fortified forward operating base in the country's east, it will serve as a "launching pad to expand military operations in the region," according to a statement issed last week by the Syrian Army.



Map source: South Front

Though ISIS lines are crumbling, US presence in the area threatens to complicate the Syrian military's forward momentum in the eastern provinces of Deir Ezzor and Hasakah. On the very day the Syrian government celebrated this key victory, US coalition 'Operation Inherent Resolve' announced its own advance on ISIS held territory in Deir Ezzor through its allied partners on the ground, including the Kurdish and Arab SDF ('Syrian Democratic Forces'). The SDF is the Pentagon's favored (largely Kurdish) proxy in the East. At times it has clashed with Syrian troops, while at others has displayed some level of tacit and loose coordination.

The US coalition/SDF force is calling its own operation - which is occurring simultaneous to regime advances - “Operation Jazeera Storm". A coalition statement issued the very day of the military airport's liberation reads as follows:

The Combined Joint Task Force Coalition welcomes the announcement by the Syrian Arab Coalition of the commencement of their offensive to defeat ISIS in the Khabur River valley, dubbed “Operation Jazeera Storm,” north of Dayr Az Zawr in eastern Syria, Sept. 9. ...Coalition forces will support the SAC during the Khabur River valley offensive as part of their ‘advise and assist’ mission, providing equipment, training, intelligence and logistics support, precision fires and battlefield advice.

The Khabur River valley lies north of Deir Ezzor. Reportedly the coalition statement at first designated Deir Ezzor city itself as the target of new operations (instead of the broader area of the "Khabur River valley") while also making reference to "anti-Syrian regime forces". But the statement was quickly altered on the coalition's press page to read the less overtly provocative sounding "Syrian Arab Coalition".

US coalition released statement Sat. saying SDF pushing into Deir Ezzur, then pulled it back, saying push was Khabur River valley 1/3 — paul mcleary (@paulmcleary) September 9, 2017

Meanwhile the SDF did make an advance in Deir Ezzor city from the north side of the Euphrates. It looks increasingly like US-backed SDF forces and the Syrian Army could be set to clash as both roll back ISIS lines from either side of the Euphrates. The SDF's surprisingly rapid advance Friday and Saturday was assisted by US and coalition airstrikes and was further made possible by the Syrian Army's weakening

of ISIS defenses on the southeast side of the river.



Map source: Syrian Civil War Maps

The airspace over Deir Ezzor is potentially growing even more dangerous as there are substantial rumors that the US coalition has declared a no fly zone (NFZ) over the north side of the Euphrates. In the meantime, Syrian and Russian air operations in the area will only increase with Deir Ezzor military airport's returning to full service.

It was nearly one year ago that the US coalition launched a massive air attack on Syrian government troops in Deir Ezzor at the very moment they were fighting ISIS. The US characterized it as a case of mistaken identity while Syria accused the US coalition of directly aiding ISIS by the attack. The incident did allow ISIS to become entrenched around the contested air base. A report by military analysts John Dolan and Mark Ames (creators of "The War Nerd" podcast) summarizes the attack as follows:

"On September 17, 2016 (just about a year ago), the USAF led a huge air strike on Deir ez Zor, featuring USAF A-10s, Australian F/A-18s, Danish F-16s, and British Reaper drones. They blasted SAA troops around Deir ez Zor, killing about 100 of them and wounding hundreds more. The attack lasted more than an hour. During that time, Russian liaison officers were screaming “Stop! Stop!” to their USAF counterparts. No response. At first the US denied everything, dragging out well-known Humanitarian Interventionist Samantha Power to call the Russian accusations a “...stunt—a stunt replete with moralism and grandstanding...” Well, folks, if there’s two things Samantha knows, it’s moralistic grandstanding. So you’d think she must’ve been right. But no. The raid happened, just the way the Russians said it did. Eventually the USAF apologized, sort of. Luckily, the media managed to be stoical about the actual death of SAA soldiers in a way it failed to maintain about fictional massacres and rapes in places like Aleppo — so the damage was easily contained, at least on the media front. As food ran short in the city, the same brave indifference characterized the response of all but a few media outlets. On the actual battle front in Deir ez Zor, the damage was more real. After the USAF & co. softened up the enemy for them, IS attacked and took several strategic hills overlooking the town. Like most victories during the long siege, though, the advantage was brief. With Russian air power helping, the SAA retook most of the ground they’d lost. This stalemate is the most remarkable thing about the war in Deir ez Zor. How do you explain it?"

As ISIS continues to rapidly collapse in its last two strongholds (Raqqa and Deir Ezzor cities), the competition for recovery of territory seems in full gear between the US-SDF and Syria-Russia alliances. Deir Ezzor province happens to be Syria's most oil-rich territory, which means the future of some of Syria's largest oil fields remains up for grabs.