Special to WorldTribune.com

WASHINGTON — Islamic State of Iraq and the Levant has dealt the regime of President Bashar Assad its biggest defeat since the Sunni revolt in 2011, a report said.

The Washington Institute for Near East Policy said ISIL has captured the Raqqa province and would soon take over the neighboring province of Dir Al Zour.

In a report, the institute cited ISIL’s seizure of the Syrian Air Force base at Tabqa, which was termed a strategic loss for Damascus.

“This stands as the most significant defeat of regime forces since the beginning of the rebellion,” the report, titled “Military Implications of the Syrian Regime’s Defeat in Raqqa,” said.

Military analyst Jeffrey White asserted that the Syrian military did little to save its positions in Raqa. White, a former U.S. Army intelligence officer, said over the last three months ISIL destroyed the Syrian military and regime militias in Raqqa, including the army’s 93rd Brigade and headquarters of the 17th Division.

“The defeat in Raqqa has major military implications — it represents a loss at the strategic, operational, and tactical levels of war, raising questions about whether the regime or Syrian rebels can defend other, more important areas of the country against further ISIS offensives,” the report, dated Aug. 27, said.

White said ISIL demonstrated its ability to conduct broad military operations within a “well-conceived strategy.” He said full control of Raqqa would enable ISIL to expand its control throughout northern Syria, including Aleppo.

“ISIL will continue to present the regime with operational challenges, and it remains to be seen if Assad’s forces are capable of responding effectively in areas of greater importance such as Aleppo City, the line of communication through Hama province, and even Damascus itself,” the report said.

The report said ISIL’s victory in Raqqa could result in the deployment of additional fighters to Iraq, where it faces a coalition from NATO. For his part, Assad failed to stop ISIL through a combination of air strikes and ground fire, successfully used against Western- and Saudi-backed Sunni rebels.

The victory in Raqqa has brought ISIL a huge amount of weapons and ammunition, including main battle tanks, artillery, rocket launchers and anti-aircraft guns. The report did not envision massive intervention in the north by the Iranian-sponsored Hizbullah and Shi’ite militias, committed to other parts of Syria.

“The most effective way to stop ISIL and then roll it back would be a combined effort involving well-armed and supported Syrian rebel forces and U.S./allied airpower, all working under a coherent long-term strategy and conducting coordinated operations to defeat the group’s forces and free areas under its control,” the report said. “Failing that, more limited measures — such as arming the rebels and using airpower to reduce ISIL forces and capabilities — would be useful in preventing more dramatic gains in Syria and perhaps rolling back the group’s recent progress in northern Aleppo.”

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