First, cut the condescension. If I wanted to be harangued, I'd call my ex-girlfriend.
Second, the withdrawal of United States troops is in fact what left Iraq vulnerable, and it was ISIS' campaign in Iraq which made them internationally famous, not Syria. We had been hearing about terrorist elements in Syria for years, now, but nobody took them seriously. The Syrian ambassador once spoke on CNN about how Assad's harsh reaction might have been a bit of an overreaction, but it was because the regime had serious concerns about terrorism in Syria and especially in the East. He was laughed at.
No, nobody knew who ISIS was until they stormed the western frontier of Iraq and took miles of land every day. Maliki (conspicuously) orders his troops to abandon Mosul (because fuck the Sunnis, right?), left all their American gifts behind, and ISIS stormed through and crucified people on the highway to signal their victory. They took oil fields. Then they got within a stone's throw of Baghdad and everyone flipped their shit. Then James Foley... etc.
All of this broke the news after the insurgency in Iraq happened, not before. I don't know why that is (world stability and terrorism should be on the front news every fucking day), but my guess is that the news of a destabilizing Iraq is more interesting than a destabilizing Syria because it adds an element to our long history with that country. In any case, if we're specifically talking about a) the coordination of attacks abroad against western countries and b) the inspiration of lone-wolf attacks when it is unfeasible to sanctioned terrorist attacks then both of those become much easier when you're on the front news every single day. I've never heard of anyone being inspired in the US by al Shebab in Africa or the Uighurs in China, or whatever the hell those muslim rebels are called in the southern Philippines. And this kind of power and wealth was possible because of their invasion of Iraq.
FURTHERMORE: they only could have invaded Iraq if there was no residual force left in Iraq from the US occupation and there was a breeding ground just across the river... which was only possible because of Syria. Double mistake on Obama's part! He should have either let Syria fall apart but keep a significant peacekeeping force in Iraq to make sure the gains were not lost, or he should have done whatever was necessary to enable a stabilizing presence in Syria, whatever form that might take. Russian influence, an Arab peacekeeping force, UN security forces, US boots on the ground, or substantial support for the Assad regime; any of the above would have been preferential to the shitshow we let happen on our watch.
Third, McCain has been for leaving a residual force in Iraq since his presidential campaign in 2008 because he actually visited Baghdad and knew what he was talking about. I don't care if Bush had a withdrawal date. Bush was wrong about practically everything in his presidency.
