ISIL lost 5,000 square miles of territory largely in northern Syria, Iraq

Gregg Zoroya | USA TODAY Opinion

After achieving explosive territorial gains across Syria and Iraq following its declaration of a new caliphate in 2014, the Islamic State group has suffered a net loss this year of 14% of what it had conquered, according to a global analysis released Monday.

Pressure from Syrian Kurdish forces and the Iraqi military, both supported by U.S.-led coalition airstrikes, have stripped the militant group of about 5,000 square miles of territory, according to the analysis by London-based IHS. The lost territory includes crucial international border crossings vital to Islamic State money-making, the analysis said.

The extremist group's fighters were driven from the Tal Abyad border crossing between Turkey and Syria, which was the group's main access point into Turkey from its de facto capital of Raqqa, Syria. It also lost a crucial highway between Raqqa and the Iraqi city of Mosul, which is in the militants' hands. That complicates the movement of goods and fighters between those two cities, the IHS analysis said.

"We had already seen a negative financial impact on the Islamic State due to the loss of control of the Tal Abyad border crossing prior to the recent intensification of airstrikes against the group's oil production capacity," said Columb Strack, senior Middle East analyst at IHS.

The military group also lost the Iraqi city of Tikrit and the vital Beiji refinery complex in Iraq.

The overall shrinking of its territorial gains comes despite the group's capture this year of the ancient Syrian city of Palmyra with its renowned Roman ruins, and the seizure of Ramadi, an Iraqi provincial capital west of Baghdad. Both were overrun by Islamic State fighters during a coordinated assault in May. Iraqi forces are slowly moving into Ramadi to liberate it from militant fighters.

Assembling forces necessary in the Palmyra and Ramadi assaults forced the Islamic State to redeploy fighters from its northern territories, leaving defenses there too depleted to withstand Syrian Kurdish attacks, the IHS analysis said.

"This indicates that the Islamic State was overstretched," Strack said.

The IHS analysis also found that the Syrian government has lost about 16% of the area it controlled before 2015. As Syria's civil war nears its five-year milestone, the forces of President Bashar Assad now hold sway over 11,500 square miles.