Whether or not "Islamic fascists" is the correct term to describe the Islamic terrorists, it is a heck of alot better than talking about a "war on terror." And, let's face it, the word "fascist" has very negative connotations for most Americans and Europeans. Putting "leftist" or "communist" after the word "Islamic" would not have the same effect. I'm really glad that Bush is openly linking radical Islam to terrorism.
He has linked radical Islam to terrorism for longer than he's used the term islamofascist.
Though islamist is more accurate, it isn't understood by the general population, and they don't make the distinction between islam and islamist.
Adding fascists gives it more punch and adds an identifiable negative term. Radical islamists? or islamic extremists? terrorist islamists? I've been working on the right name (unsuccessfully), too.