Except Syria has been Russia's turf for decades. We have no interest there. We had an opportunity to inject ourselves when this whole thing kicked off, but Obama pursued regime change after so many wonderful successes during the "Arab Spring." Syria's been in chaos ever since.
Oh no doubt. And so was Ukraine. Obama didn't expect Putin to push back, but after he saw what happened to Libya, he pushed back in Syria for sure. Crimea and the Baltic have been a 350+ year project for Russia, so to expect any leader in Russia to give it up was just sheer Obama stupidity and neocon fantasy.