My high school band director was fond of saying "if you are going to make mistakes, it is more to your credit to make a different one every time".
Osama bin Laden goaded America into getting bogged down in an unending, unwinnable war in Afghanistan for the purpose of draining our resources and enhancing the status of al Qaeda and the recruitment of jihadists. The US exceeded his wildest expectations by also invading and occupying Iraq.
ISIS is doing the exact same thing as al Qaeda. They want us to invade and occupy Syria and re-occupy Iraq. They don't care if they are pushed out of there. They know that once the US has invaded, we can never leave, ever, because of the void that will be created and the unavoidable fucking mess that will ensue. As soon as we get bogged down in Iraq & Syria, if not before, they will pop up in places like Yemen, Oman, Afghanistan, Egypt, Uzbekibekistanstanstan, and God knows where else, luring us into an ever larger and ever more costly conflict.
Lately, I've been seeing stuff like this from my liberal friends:
"Sometimes brute force is the only answer. ISIS has reached that point. I'm all for destroying them."
That is exactly the response that ISIS is angling for. We are playing into their hands. They are counting on the innate inability of the worlds greatest military power to exercise military restraint. History is repeating itself, and it isn't going to work out any better for us this time around.