Kuwait City, Kuwait — A desolate outpost in southeastern Syria used to belong to ISIS. But now it's in the hands of American special forces. CBS News was there with Gen. Frank McKenzie, commander of U.S. forces in the Middle East.

From a compound, still choked with rubble from the battles here, special forces travel out to even more remote outposts to train local tribes to hunt down the remnants of ISIS.

"They try to get in the desert up here, and our partners go out and get 'em and we help 'em do that," McKenzie said.

It's been four months since the last piece of ISIS-held territory was liberated and there are still nearly 1,000 U.S. troops in Syria. The main American base is in northern Syria, where a strip long enough to handle jet transports has been carved out of the Syrian plain. It's industrial strength logistics only the American military can do and there's no end in sight.

"We don't want to stay here any longer than we have to but there are still some ripe targets out there and we are going after them," McKenzie said.

Nothing here is easy. Fall rains turn this dust to ankle-deep mud. The V-22 Ospreys that flew CBS News out of Syria had to refuel in the air in order to make it.

ISIS may be on the run in Syria, but it is still alive and dangerous. A U.S. official said there are still suicide attacks and roadside bombings in areas that were liberated from ISIS.