We are all entitled to our opinion sexeducation, and the opinion that Bush lacks intelligence, judgement and most of the other things that makes a good president is a popular one.
Why? If you've followed the news at all, you'll know that Bush went against a UN resolution to attack iraq under the claim that there were weapons of mass destruction.
So far there hasn't been any evidence that iraq possesses WOMD, billions of dollars were spent fighting the war, and billions more will have to be spent rebuilding it. So yes, people have a right to assume that Bush is incapable of making sound decisions. Destorying Iraq was simply a way to impress daddy for Bush.
Questioning his intelligence? Well, if you haven't seen this clip, have a look at Bush's performance:
http://msnbc.com/m/mw/mw.asp?0mw=xh6...&sk=&pl=&cp1=1