The Queen is in a very strange position in this country. As she is the head of state, it would have been very strange (and quite insulting to President Bush) if she had not met with him.

However, she also stays as apolitical as possible. Which means if the Prime Minister and the government (who technically work for her, and swear allegiance to her) set up a meeting for her with someone, she tends to turn up. She doesn't pick and choose.

And, to be honest, whatever my personal opinions of President Bush are, there's no doubt that having the President of the US visit Britain is a significant occurrence and there should be a level of pomp and ceremony to accompany it.