...Bush stated his support for the ban during the 2000 presidential campaign but stopped short of pledging to sign an extension.
That's not true. He promised to sign it if Congress put it on his desk.
Bush Backs Renewing Assault Weapons Ban April 12, 2003
VPC Welcomes President Bush's Support of Reauthorization of Federal Assault Weapons Ban April 14, 2003
Hear it from his own lips.
G.W. Bush was for assault rifle ban & closing gun show loophole Youtube video 0:27