Honestly, we've heard all this Illuminati and World Bank stuff before. Franklin Roosevelt was a tool of the Worldwide Jewish Banking Conspiracy and conspired in the Pearl Harbor Attack in order to provoke US entry into World War 2, right?
There is a seed of a theory in the film. If Prescott Bush was involved with Nazi money-laundering, that is truly scandalous. But it doesn't logically follow that his grandson is a disciple of Hitler. Juxtaposing pics of Bush and Hitler kissing babies doesn't prove anything except politicians kiss babies. If the Bushes are exerting fascist control of the government, how did their minions allow things to get so out of control that they lost control of Congress in the midterms? And if something went wrong in their nefarious plan, why weren't there troops in the street on November 5? Does the Bush Administration's continued lop-sided support of Israel reveal Hitlerian motivation?
I'm sure if you really buy this stuff you can answer all of those questions. Conspiracy theory has much in common with religion ; it must be approached from a position of emotion and faith. Inductive reasoning can then fill in the blanks for you. In a way, it's like Bush's argument for invading Iraq. The same sort of thought process.