Good question.

President Carter wrote an op-ed piece for the New York Times on Sunday.

The evolution in public policy concerning the manufacture, sale and possession of semiautomatic assault weapons like AK-47s, AR-15s and Uzis has been very disturbing. Presidents Ronald Reagan, George H.W. Bush, Bill Clinton and I all supported a ban on these formidable firearms, and one was finally passed in 1994.

When the 10-year ban was set to expire, many police organizations -- including 1,100 police chiefs and sheriffs from around the nation -- called on Congress and President George W. Bush to renew and strengthen it. But with a wink from the White House, the gun lobby prevailed and the ban expired.