Some of the century's most infamous crimes have led to new gun-control laws.

Gang shootings and an assassination attempt against President Franklin Delano Roosevelt in 1934 moved Congress to restrict machine guns. The assassinations of Sen. Robert Kennedy and the Rev. Martin Luther King Jr. fueled laws against cheap, imported "Saturday Night Specials" in 1968. President Bush barred imported assault weapons in 1989 after a man killed five children with an AK-47 at a California playground.Now, gun-control advocates sense an opportunity after recent school shootings in small-town America - Pearl, Miss., Jonesboro, Ark., West Paducah, Ky., Springfield, Ore., and at a school dance in Edinboro, Pa.

That has the National Rifle Association, gathering Friday in Philadelphia for the start of its annual meeting, girding for another battle.

"In the wake of a tragedy, it seems there are always some who spring forth and grab a headline with the quick, easy legislative answer," NRA spokesman Bill Powers said. "And, quite frankly, the problem of troubled youth and violence is a problem that's not addressed by the quick, easy legislative answer."

But gun-control advocates believe the recent spate of kids shooting kids has altered the political playing field.

"I think this is a different kind of event," said Bob Walker, president of Handgun Control Inc. "What happened in Jonesboro, in Edinboro and in Springfield has led many gun owners to the realization that the problem in America is not just the guns on the street. It's the guns in the homes."

"It goes beyond legislation," Walker said. "Legislation can help to reinforce that, but fundamentally we have to plead with gun owners to recognize the dangers of having a gun in the home."