Barack Obama gets a free pass for his war mongering, even from the political left, as described by Glenn Greenwald:
Most Democrats are perfectly aware of Obama’s military aggression. They don’t support him despite that, but rather, that’s one of the things they love about him. After years of being mocked by the Right as Terrorist-coddling weaklings, Obama — strutting around touting his own strength — lets them feel strong and powerful in exactly the way that Bush and Cheney’s swaggering let conservatives prance around as tough-guy, play-acting warriors. Rather than ignore this aggression, Democratic think tanks point with beaming pride to the corpses piled up by the Democratic Commander-in-Chief to argue that he’s been such a resounding foreign policy “success,” while Democratic pundits celebrate and defend the political value of his majestic kills.
It doesn’t pay for Democrats to actually please progressives on war issues. Republicans don’t turn on Democratic Presidents when they wage war. They’ll express misgivings, but at least half of them will back him fully or limit their criticism to “he should have gone to war faster!”, which is what happened with Libya.
So if the progressives won’t hold your feet to the fire, and Republicans won’t turn on you, then it becomes logical as a Democratic President to wage a lot of war. It’s a win-win proposition, politically.