American political leaders following the money drift tend to want to allocate defense contracts and munitions expenses as a primary method for interdicting foreign policy activities demonstrably harmful to U.S. national interests. In the development of ISIS following the lack of foresight of the Obama administration when it supported increase of the Syrian civil conflict several years ago and since a new circumstance presents that the U.S. Government administration feels would be best met with direct U.S. counter-insurgency activity. The reasoning is not unlike that of the Bush administration in its middle east policy or that of the Obama administration in Libya too-that is, though it is possible to engage in conflict and find someone to bomb the political consequences of a vacuum of power created by conflict are not well considered.
When the United States enter conflict even through proxies it may create a power-vacuum when it completes its mission stimulating further conflict. It would be better to reinforce existing governments in Syria and Iraq than to speculate on fast-shuffling regime changing casts of players that may hypothetically bring in a new era of business with U.S. and European corporations after taking power. Certainly while the United States sponsors training of rebels and a continuing war against the Syrian Government it is unlikely that terrorism will stop developing or that peace will take hold soon.
While it might be possible to reinforce and develop the Kurds of the region and move them toward a better semi-autonomous status and take up some of the slack enabling the ISIS international terrorists to swell to the point of claiming sovereignty it is too obvious that the conflict in Syria must be halted right away with the U.S. at least withdrawing all support for aggression against the Syrian government. Training another generation of international terrorists to run about the Middle East will not advance American long-term political interests nor those of virtually any existing Middle Eastern government.