Because Europe would be happy at the expense of our own interests... i.e. safety. Im sure Kerry would let all the EU countries into Iraq to profit from the duty of our troops. Thats one of my favorite bush-happenings.
Germany/France: Screw going to war.
Bush: Alright. We don't need you.
*3 months later*
Bush: Sweet, we won.
Germany/France: Mind if we come in and get some nice reconstruction contracts and oil revenue?
Bush: F*ck off.