Do-it-yourself has never been easier; just ask the owners of any of the more than 25,785 ghost guns seized nationwide last year. The internet has made it simple for Americans of all ages (and criminal records) to purchase firearm-making kits at discount prices. The result is a national crisis.

The Post reported this month on a rash of crimes using unlicensed, unserialized weapons: from an 18-year-old in Springfield, Va., who stormed into a garage during a fistfight and killed two unarmed 17-year-olds; to two teens in Brooklyn Park, Minn., who tried to shoot someone outside their car and killed their friend inside it instead; to a 16-year-old in New Rochelle, N.Y., who created a “factory” for firearms in his bedroom last year before killing one of his peers. The Bureau of Alcohol, Tobacco, Firearms and Explosives has connected ghost guns to 692 homicides and fatal shootings through 2021. But authorities can’t link the guns to suspects, because they have no serial numbers to identify them.

The spectral nature of these weapons is a selling point for criminals who don’t want to get caught. It also helps those who can’t buy guns from licensed dealers. That includes people who would fail background checks, such as convicted felons or violent extremists. And it includes people too young to own guns legally. Manufacturers’ ability to ignore the usual rules surrounding firearms sales depends on a regulatory loophole: They argue they’re not selling guns at all. Instead, they market “frames,” for handguns, and “receivers,” for rifles — each of these constituting 80 percent of a gun rather than a gun in its entirety.

Turning one of these into a 100 percent complete gun is a breeze with an online tutorial. Even a novice can produce a Glock 19 or AK-47 in a few hours. Sometimes they have to buy the extra parts separately, but often they can opt for a package deal with the components included.

There is no good reason federal policy should allow anyone with an ounce of web-savviness to skirt the law. The good news is that the White House published a rule last summer clarifying that frames and receivers qualify as firearms under the Gun Control Act of 1968. The bad news is that a federal judge in Texas vacated the stricture as an abuse of the ATF’s authority. Wiser minds might prevail on appeal, but Congress has room to act, too, by affirming that frames and receivers are firearms that require serial numbers as well as background checks on buyers.

The other option is for the states to act. Thirteen have already imposed regulations on ghost guns. The best approach is to ban the sale of unfinished firearms without serializing their parts and performing background checks, as well as possession of unserialized parts or completed products. States and cities with laws in place can take to court ghost-gun companies that ship into their borders anyway, just as Los Angeles did when its police department recovered more than 700 such weapons sold by Nevada-based Polymer 80. The District received a $4 million judgment in a similar suit.

Arguing against closing the loophole on ghost guns means arguing that dangerous criminals and reckless children should be able to log on to their computers and buy weapons of war. Is the gun lobby ready to make that case?

This editorial first appeared in The Washington Post on July 18, 2023. It was distributed by The Associated Press.