9/11 occurred in FY-01 and that was a Clinton budget. Hasn't the Defense Budget nearly doubled since then?
The FY 02 budget was the one Rumsfeld was working on. He put in the money to pay for Clinton's drawdowns on weapons stocks for Yugoslavia and Desert Fox, plus a small pay raise IIRC, and it added up to $60 billion. Bush told him to take it all out and pass the word to the armed services: Stand fast on budget requests. He dishonored his campaign pledges to the People.
Then he went back to Rumsfeld that summer with a demand for a $60 billion carve-out from existing programs and priorities for SDI. That was a $120 billion swing.
All that happened before 9/11.
Don't get me wrong: I think SDI on balance was probably a good thing to do. But standing down the total budget and dishonoring your campaign promises on defense so you could do tax cuts for the Yacht Club crowd?
Hasn't the Defense Budget nearly doubled since then?
As a series of war budgets, yes. But you can't do what Bush did at the outset, and then have issues come up like the vehicle-hardening issue and guys going through the scrap-iron heap, while you're still fighting hardest for tax cuts like you were before it all hit the fan. That is NOT cool.