I didn't like Bush and didn't vote for him, but I think the real road to Trump, wasn't Bush, but Obama.  It was a mix of the freak out that a black man with a funny sounding name was now President and people who just hate everything that is left of center.  Those 2 groups metastasized into the Tea Party which did a bang up job at stopping Obama at every turn.  Couple that with the right wing scream machine and you had the perfect storm.