In two cases we know of, one in Syria and one in Iraq, ISIS was holding captives. That meant the location could not just be destroyed, so a planned raid by special forces was the only way to free them and kill or capture the jihadists. I doubt these forces will be involved in direct action like that if they are working with local troops in northern and eastern Syria, or maybe in parts of Iraq. But several dozen special forces members used that way can have an effect far out of proportion to their numbers. They used Ospreys for the raid into Syria, and that might be one way to resupply them--fast, and no landing strip needed.
Part of their job may be to teach the locals some tactical skills that will make them more effective, and let them do the infantry fighting. That may be necessary where ISIS forces are so close to civilians that heavy weapons would kill a lot of innocent people. Even there, the U.S. forces may bring along weapons like portable missiles that would give the locals a big edge against a point target, say a building jihadists were firing from.
But the special forces can also use heavy weapons to kill the jihadists, so the local troops would, at least some of the time, have the much easier task of just moving up and taking control of whatever ground ISIS had been occupying. The U.S. forces will be able to call on all sorts of assets, including reconnaissance from satellites or U-2's. They can use drones to watch places where intelligence, maybe some of it gathered by the local troops they are working with, suggests there are ISIS forces. If they verify that there are, they will then be able to laser designators to pick them out in some cases, or where there is no direct line of sight to them, use a drone to designate the target.
Once that has been done, that or another drone might use a light missile, a more powerful one, or even a 250-lb. bomb against the target, depending on how much force was needed. And in cases that called for more yet--say where a lot of jihadists were found spread out in an open area, or in a convoy of vehicles, or in a large or fortified structure, the special forces could quickly call in aircraft with larger bombs, cluster bombs, etc. They could easily be miles away from the targets, without the ISIS forces ever even knowing they were there.
