FactCheck.org does a piece on Kerry's criticism of Bush for "letting the assault weapons ban expire":

A new Moveon PAC ad implies machine-guns are becoming legal, which isn't true. And it blames Bush, even though Bush said he would have extended the ban on assault weapons. September 14, 2004 Modified: September 14, 2004 Summary This latest ad from Moveon PAC is about as misleading as it can be. Through words, graphics and sound effects, it invites viewers to think that the expiration of the ban on 19 semiautomatic assault weapons will allow people legally to buy fully automatic machine guns that can fire "up to 300 rounds per minute." That's false. It has been illegal to buy a machine gun without federal clearance since 1934, and remains so. The ad also claims that Bush "will let the assault weapon ban expire," which is misleading. In fact, Bush spoke in support of the ban during his campaign four years ago and his spokesman said as recently as May of last year that he still supported it. It was Congress that failed to consider extending the ban and didn't present Bush with a bill to sign.

Technically, FactCheck is completely correct. The Move-On ad is misleading and Bush didn't actively cause the ban to expire. You can't argue with FactCheck.

However Bush did inactively allow the ban to expire, in the best interests of the NRA, not in the best interests of the people for whom he works (American citizens). Bush swore in 2001 to protect the citizens of the United States. The Presidency is an active job, not a job where one sits around letting things happen. In this case Bush let things happen. A role of goverment is to protect those who cannot protect themselves, and Bush totally failed the test on this issue. He should be raked over the coals for allowing the expiration of a ban that had saved hundreds if not thousands of lives during the ten years it was in effect. Bush once again proves that he has no respect for any of our lives, unless of course our living involves sending money to the GOP. Since the day Bush took office I have yet to see him do one humane thing, one that did not involve a photo-op. Bush has become the most dispassionate President in the history of the United States and will no doubt be remembered throughout eternity for his blatant and extremely consequential prevarication and hypocracy.