The United States is warning that crushing the Islamic State’s self-declared caliphate will not be enough to deal the terror group an enduring defeat – a message Washington delivered even as it pulls the majority of U.S. forces from Syria.
U.S.-back forces declared victory over the IS caliphate Saturday, liberating the northeastern Syrian town of Baghuz after unleashing a series of airstrikes against several hundred fighters who refused to surrender.
Since then, the Syrian Democratic Forces have been involved in clearing operations, carefully sifting through what is left of the terror group’s encampments for explosives and booby traps, as well as searching a complex network of caves and tunnels that were used to hide thousands of fighters and their families until the town’s fall.
Yet despite the optimism expressed by numerous coalition officials, the U.S. special representative for Syria cautioned a lasting victory is not yet within sight.
“This is not the end of the fight against ISIS,” U.S. envoy for Syria James Jeffrey told reporters Monday, using an acronym for the terror group. “That will go on, but it will be a different kind of fight.”
"They're reconstituting in small groups, operating in the shadows as a low-level insurgency," he said, adding that the full impact has yet to be felt in Syria, where the group’s remaining forces “are in shock from having lost this terrain.”
Jeffrey, as well as other coalition officials, estimate Islamic State still boasts an estimated 15,000 to 20,000 fighters spread across Syria and Iraq, though he cautioned such estimates are “not worth the paper they’re printed on.”
U.S. officials had previously estimated IS had, at its height, up to about 34,000 fighters. But Jeffrey said Monday that number could have been as high as 100,000.
Other senior U.S. and coalition officials have also admitted their ability to estimate the size of the radical Islamic group's fighting forces has been limited, predicting most recently hundreds of fighters were left to defend Baghuz when, in reality, thousands were killed or had surrendered.
“We have been consistently wrong, as have our SDF partners, on how big this is,” a senior defense official said.
Region Remains Fertile Ground for IS
So too, there are concerns that the region remains a fertile ground for Islamic State, which has learned to play upon local grievances as well as anyone.
“The political conditions haven’t changed really dramatically from the 2009 perspective,” said Craig Whiteside, a senior associate with the Center on Irregular Warfare at the Naval War College. “In some cases, they’ve actually gotten worse.”
Potentially making IS more dangerous, according to Whiteside, is that the group has successfully carried out an insurgency before and, at least in the past, has been patient enough to see it succeed.
“They don’t have timelines in their strategic documents. They just have an understanding that they’ll do it until it works,” he said.
At the same time, officials and analysts warn Islamic State has been preparing for this new insurgency for more than a year, starting before the fall of Mosul, its capital in Iraq, in June 2017.
But at least in Syria, U.S.-backed forces will be taking on the new fight without the same level of support.
"Armed forces are being withdrawn," Jeffrey said Monday, explaining some of the 2,000 U.S. troops that had been stationed in Syria have already been pulled out – in line with the plan announced by President Donald Trump in December.
U.S. officials have said the residual force, likely about 200 troops, will be stationed in northeast Syria and at al-Tanf, a U.S. garrison in southern Syria that is seen as key to stopping smugglers supporting IS as well as limiting Iran’s influence in the region.
There have been talks between the United States and its coalition partners to set up a force of about 1,500 troops to help the Syrian Democratic Forces continue clearing operations and other stabilization efforts.
U.S. officials have characterized the talks as positive. Only the plan has met with some criticism from allies, like France, which complained last week that many questions about the size, make-up, and mission of the proposed force remain unanswered.
Jeffrey on Monday pushed back against those concerns, saying the United States was getting a “pretty good response” to its request for allies to “up their contribution.”
He also rejected a call by Kurdish authorities to set up an international tribunal to prosecute foreign fighters who joined Islamic State but who have not been taken back by their own countries.
“We’re not looking at that right now,” Jeffrey said, insisting the U.S. focus remains on making sure foreign fighters are sent back to their countries of origin.
“If they put the effort in, they could do it," he said.
The SDF is holding an estimated 7,000 IS fighters. More than 1,000 are thought to be from countries other than Iraq and Syria.