You don't think creating a power vacuum in the Middle East is Bush's fault?
Weird.
You've got the partisan thing really bad.
Bush was out of office when the power vacuum occurred. Iraq was relatively stable when Obama took over. Those are two facts.
If you want to make it about Bush, Bush spelled out what would happen if we pulled out of Iraq:
“To begin withdrawing before our commanders tell us we are ready would be dangerous for Iraq, for the region and for the United States" [Bush: 2007]
So there's actually two people at fault for the power vacuum: Bush, for creating the potential for one in invading Iraq: and Obama, for failing to keep Iraq secure. Obama is the one who actuated the potential initiated by Bush.
Put simply: the vacuum occurred under his [and Sec Clinton's] watch. Fact #3
Along comes ISIS: they nearly literally come waltzing out of Syria in their little Mazda trucks outfitted with artillery and began to take over Iraq.
And Obama does what he does best. He minimized the threat and called ISIS 'JV'. A gross miscalculation, which led to an ensuing genocide of various tribal groups, including Christians and Kurds: there was and continues to be massive blood letting, decapitations, crucifixions and probably things we'd rather not imagine going on in the, once stable, Iraq.
To make matters even worse, ISIS has become a sort of global terrorist beacon which every sort of malcontent swarms to like moths to a candle. Since ISIS isn't not only represents a caliphate but an ideology, we have an unknown number of sympathizers here in the US.
The FBI snagged one yesterday in NC. He wanted to start his own ISIS cell.
The bad news is we'll never catch them all. To lay all that at the feet of Bush is sheer partisan hackery.