It took a massive killing by a gunman in Las Vegas last year who used bump stocks in his arsenal of weapons in a shooting outburst at a country music concert to bring about a ban on the firearms attachment. The gunman killed 58 people.

President Donald Trump has banned bump stocks, the attachment to semi-automatic weapons that allows them to fire like machine guns.

Bump stocks became a lightning rod in the gun control debate after the worst mass killing and wounding of people in this country at Las Vegas last year.

The ban will take effect 90 days after it is published in the Federal Register. Bump stock owners will be required to destroy the attachments or turn them in to the Bureau of Alcohol, Tobacco, Firearms and Explosives. ATF estimates that between 280,000 and 500,000 have been sold since 2010. ATF admits that there is no way the agency can be sure owners comply with the ban.

After the Las Vegas shooting, there was an effort in Congress to ban the attachments, but no law was passed. Some states sought their own bans.

The federal government expects the ban to be challenged in court. The Justice Department said it will fight any legal challenge to the ban. The National Rifle Association wants the Justice Department to provide amnesty for gun owners who already have bump stocks.

The largest maker of bump stocks announced months ago that it would not take any more orders for bump stocks, which still are available from another company in Texas.

A weapon with a bump stock is not needed for protection by any citizen. It’s like a machine gun. The protection argument for having a gun with a bump stock attachment makes about as much sense as saying the new Highway 47 bridge at Washington will be under floodwaters.