Imagery acquired by Stratfor working with its partners at AllSource Analysis illustrates the damage inflicted by an Islamic State infiltration attack on the Syrian loyalist air base at Deir el-Zour. A relief force recently reached the base and the Deir el-Zour garrison, which had endured more than three years of siege by the Islamic State. As can be seen from the attack, however, the Islamic State still maintains the capability to inflict damage and carry out attacks in the region even as it has technically ceased to control territory around Deir el-Zour and its airbase.
On Nov. 13, reports from loyalist sources indicated that the Islamic State had conducted a suicide infiltration attack on Deir el-Zour air base. Subsequent reports from loyalist sources in the days after the attack highlighted how a vehicle full of Islamic State fighters dressed as Russian troops and speaking Russian successfully talked their way onto the base before initiating their surprise attack. Satellite imagery from Nov. 18 depicts the aftermath of the attack, illustrating how the Islamic State fighters were able to penetrate about 600 meters through checkpoints, security fences and defensive fighting positions before reaching their key targets, the L-39 trainers used as light attack jets by the Syrian Arab air force. The attackers appear to have inflicted considerable damage, destroying up to four of the jets, which airbase personnel look to have subsequently pushed off the aircraft aprons. As of Nov. 18, satellite imagery points to six L-39 jets still being operational at Deir el-Zour air base, although one of these jets appears to have been lost in a crash on approach to the base on Nov. 21. All told, the Syrian Arab air force likely lost half of its L-39s at Deir el-Zour over the span of a couple of weeks, greatly reducing its capacity to provide air support for local counterinsurgency operations.
The Nov. 13 Islamic State attack highlights how the extremist group will remain a key threat even as it is defeated on the battlefield in Syria and Iraq. While the Islamic State has effectively lost its ability to act as a powerful conventional force that can seize and hold terrain against determined attacks, it has not lost the ability to pose a threat through insurgent and terrorist-style attacks. The Islamic State will take advantage of the large and poorly governed spaces in eastern Syria and western Iraq and the porous border between the two countries to maintain a simmering insurgency in the region, much as its predecessor did in Iraq after the withdrawal of U.S. forces in 2011.
The underlying reality of a continued threat from the Islamic State underscores the desirability of a solution to the Syrian civil war as well as stability in Iraq that would allow the regional parties to focus their efforts on preventing the return of the extremist group rather than on battling each other.