What if 9/11 happened two years earlier than it did OTL? How would Clinton respond? Would a McCain Presidency be garanteed? Would McCain say, "I served, therefore I'm fit to handle this crisis"?
I think Bill Clinton would've been the best bet for a "One war at a time" kind of policy, George W. Bush would probably follow the same policy, however our best bet for a sane Republican is John McCain and he is pretty moderate.
Assuming 9/11!1999 has the same rally around the flag, but with Clinton's 'War on Terror' being a beef up of his IoTL efforts, then wouldn't it be far more likely that Gore would be the next President?