I tend to agree here. Hitler gets dragged into too many debates as a comparison point. Bush is no Hitler. Neither was Saddam. Saddam didn't have the economic/military clout to become a Hitler, even if he might have been as evil. Bush hasn't displayed a lack of morals or evil on the scale of Hitler, and his crimes don't compare with Hitler's.
That said, Hitler didn't start gassing Jews the day he was elected. Nor did he invade Poland in 1933. One small step at a time, he edged his way into dictatorship, militarism, expansionism, and genocide. And each incremental step was a relatively minor change to the previous status quo, leaving his opponents with nothing concrete to use as a rallying point against him - until it was too late, of course.
That's what makes things like extraordinary rendition, Guantanamo, the 9/11 inconsistencies, the Patriot Act, the invasion of Iraq, etc., somewhat worrisome. The blueprint is out there. That doesn't mean Bush will become a Hitler - he certainly doesn't seem to have either the drive or vision that Hitler did, and I optimistically assume he doesn't have the malice that Hitler had. But he should be watched carefully and the anti-constitutional, unilateralist aggressions of his administration checked where possible. Just in case.