KOBANI, Syria -- A dirt airstrip for the U.S. military and a storage space for over 100 tons of munitions is carved out of the desert in northern Syria. It's an American logistics hub for the fight to retake Raqqa -- the so-called ISIS capital -- that began almost a month ago.

Lt. Gen. Stephen Townsend, the commander of the U.S.-led coalition to fight ISIS, came straight from a forward command post near Raqqa.

"I think we're in the first 25 or 30 percent of the campaign for Raqqa," Townsend told CBS News. "We're just getting started good in Raqqa."

As U.S.-backed fighters close in on ISIS from the north -- where they've also clashed with Syrian regime forces, which are backed by Russia -- there are fears that the U.S. and Russia could be drawn into a direct conflict.

But the general downplayed that risk.

"We've worked out a deconfliction line with the Russians and the regime and they seem content to let us work on the Raqqa problem. And we've drawn a line and they're happy to work on their side of it, and we'll work on our side of it," Townsend said.

Gen. Townsend promoted a young officer to first lieutenant on Wednesday -- and he acknowledged to CBS News that U.S. troops won't be leaving Syria any time soon.

U.S.-led coalition forces in the fight to re-take Raqqa. CBS News

"I think U.S. troops will start leaving Syria when ISIS is defeated," Townsend said.

But will ISIS turn into an insurgency when they've lost all their territory?

"I think that's the next stage of ISIS," Townsend said. "We call that ISIS 2.0 -- an insurgency, rural. So I think we'll still be here dealing with that problem set for a while."

ISIS and its cult of barbarity may be difficult to eradicate entirely. But Raqqa was used as an operations base to launch terror attacks on the West – and the U.S. hopes by retaking the city, it will prevent future attacks.