Just blame Bruce Lee.

Back in 1974, New York state decided to ban the possession of nunchucks as lawmakers feared they were becoming enticing tools of violence among hooligan children and street criminals who were exposed to the weapons on TV. They were so dangerous, lawmakers believed, that not even karate teachers could keep them in a locker at home.

But while being dangerous might have been a good enough reason then, it doesn’t cut it anymore, as a federal judge ruled Dec. 14.

In a 32-page ruling, U.S. District Judge Pamela Chen struck down New York’s nunchuck ban as unconstitutional, finding that nunchucks are protected under the Second Amendment right to bear arms.

Chen concluded that nunchucks are commonly used by law-abiding citizens — for example, by karate enthusiasts, or for self-defense — so therefore banning them outright runs afoul of the Second Amendment. The judge also applied a 2010 landmark Supreme Court ruling that extended the Second Amendment to state laws.

But while the nunchucks ruling may be an important affirmation of those principles for gun rights advocates, after nearly 15 years of litigation, the ruling also represents a long-sought victory for one New York amateur martial artist.

James Maloney, who is also a lawyer, had been arrested for possessing nunchucks at home in 2000. Since 2003, while representing himself, he has argued that the law prevented him from teaching his children specialized karate moves that he invented, involving use of the nunchucks. He called his style “Shafan Ha Lavan.”

Maloney’s children are now grown. But his goal in the case extended well beyond passing down a martial arts style to his sons. He believed that the government’s total ban on nunchucks in the home stripped him of the right to defend himself, which the Supreme Court has said is a central principle of the Second Amendment.

Even though he only asked that Chen recognize his right to at least keep nunchucks at home, the judge went a step further, finding the entire law targeting nunchucks to be unconstitutional.

“The Court granted relief somewhat beyond what I had asked for, but I am not about to complain,” Maloney wrote on his blog, where he has been chronicling his one-man nunchuck battle. “Thanks to the many who have helped in many ways along the way. It has been a path with heart.”

The ruling, if left in place, would make Massachusetts the only state to still ban the karate weapon outright, according to the ruling, though other states restrict the use of nunchucks in varying ways.

Kung fu was all the rage in 1974, when New York state lawmakers debated adding nunchucks to its list of banned weapons, joining machine guns and brass knuckles.

Bruce Lee’s death in 1973 was still fresh and so was his last film, “Enter the Dragon,” which was released a month after he died and immortalized as one of the best kung fu films of all time.

The TV series “Kung Fu” was in full swing too.

And “The Street Fighter,” premiering in 1974, surely horrified lawmakers concerned about nunchucks, as it was the first American film to earn an X-rating purely for violence.

Until now, nearly all the state needed to do to uphold its nunchuck ban was prove that it was rationally related to a government interest, such as keeping citizens free from nunchuck attacks.

Attorneys for the Nassau County District Attorney’s Office, the jurisdiction where Maloney was arrested, attempted to argue that “the dangerous potential of nunchucks is almost universally recognized.”

But Chen didn’t buy it.

Chen wrote: “The centuries-old history of nunchaku being used as defensive weapons strongly suggests their possession, like the possession of firearms, is at the core of the Second Amendment.”