The Patriot Act was crafted under the Clinton regime and was on the shelf waiting - 9/11 gave the statist politicians in Washington - Democrat and Republican alike - the opportunity to implement their big government/Orwellian wish list.
Let's not forget..
George W. Bush is NOT a conservative..
He is a moderate..
The only thing he has in common with conservatives is "party affiliation".. He's a republican..
But more than that, he's just as you said.. a big-government politician.. ( A "federalist" ? )
So what has changed?