Justice Antonin Scalia, speaking for the court, said the history of the 2nd Amendment shows its authors intended to protect the "right of the people" as individuals to have weapons, both to defend themselves and their community.
The ruling is the first in the high court's long history to strike down a gun law based on the 2nd Amendment.
But the court's ruling appeared to be narrow. Scalia stressed that nothing in today's decision casts doubts on laws that forbid felons or the mentally ill from having guns.
He also said the government can strictly regulate when and where people have guns. For example, he said guns may be prohibited near schools and in or near government buildings.
"Like most rights, the right secured by the 2nd Amendment is not unlimited," Scalia said.
It is unclear just what the impact of the ruling will be. It may be that the biggest impact is to take an issue away from the November elections for the NRA folks.
