One of the most dangerous things in the world is a politician with strong beliefs. They believe they know best, ignore evidence to the contrary, and ignore the opinions of others. Then they do stupid things that affect all of us.
Religion is based on beliefs, and strongly religious politicians tend also to have strong belief in their own right to impose their beliefs on other people.
In many ways Tony Blair has one of the best records of a prime minister in recent British history. He has done a lot of good for the country, however he is now very unpopular because he let his beliefs guide him when he should have been listening and using his intelligence. He is an overtly religious man, more so than most recent British politicians, and he also stubbornly sticks to unpopular policies that he believes are right. While it did make sense to be politically close to the USA, he took it too far for too long, and took Britain to war on false pretences, because he believed too strongly in the fake evidence of WMDs.
The US administration, especially Bush, Cheney, Rumsfeld and Rice are so fixated on their beliefs, that they will do anything to deny and supress evidence that doesn't agree with them. They even deny that they said things that were clearly said on the record, as The Daily Show gleefully points out with back to back video clips. There is a complete inability to admit that they could ever be wrong on anything.
I want all politicians to be atheists, with weak belief systems, and an ability to solve problems, analyze evidence, change their minds if necessary, admit their mistakes quickly and make policy with an open mind and an inclusionary and pluralist attitude. Then the people of America and the world will be truly free.