And away we go.

Onions are more important than George W. Bush's daughter. Bush was President of '04, right? RE4 is set in '04?

The president of the United States in RE4 was a man named Graham, the same last name as Ashley. It's common practice in all but a few instances of media to cast fictional characters in actual US politicians' places. The only exceptions I know of were the television series JAG which had actor David James Elliot digitally inserted into a scene with former president Bill Clinton and Transformers which had a George Bush impersonator cast for a brief scene aboard Air Force One.