outside of Syria, you could only argue that the aggression of Russia has been his glaring foreign policy flaw.
Obama's foreign policy and leadership at state has been a complete mess, stirring up hornets nests all over the world.
He doesn't want to meddle, but at the same time he wants things to turn out a certain way. So he's willing to bomb people we don't like and train their enemies, but he doesn't want to actually be committed to anything that might reflect badly on him if it went pear-shaped. You can't make alliances when your potential allies are (justifiably) worried you'll bug out at the first sign of adversity.
Obama seems to come from a totally different place. I think there has been a lot of bumbling and trying to lead by tracking polls. Egypt was a perfect example of this, Hozni Mubarak and the Egyptian military got mixed signals and then got thrown under the bus because of public polls, as far as I'm concerned. Expedient to make him look populist, but also reckless.
Beyond the bumbling, I think the Obama is all about upsetting the existing order. He's into fundamental transformation, it's his thing. Wars and allowing hegemony to form that is natural for a region, like Iran in the middle East, is ultimately what he wants to see.