The nation’s police forces should be the first to rally behind a federal proposal to ban the sale and manufacture of the 5.56-millimeter steel-core bullet. The bullet can be used in newly adapted handguns to provide lethal force to pierce the vests and body armor used by law enforcement officers.

Until now, the powerful “M855 green tip” bullet has been legal for use in AR-15 semiautomatic rifles, typically used by target shooters and hunters. But the gun industry’s reckless development of new handguns that use the bullet — criminals prefer handguns over rifles — has led the Bureau of Alcohol, Tobacco, Firearms and Explosives to sensibly propose banning it in the name of greater gun safety.

Predictably, the gun lobby is marshaling gun owners and legislative allies to oppose the ban, falsely accusing the Obama administration of exceeding its authority through some backdoor attempt at gun control. The law, however, is clear: Armor-piercing handgun ammunition has been banned since 1986, and the firearms agency has the responsibility to regulate the law’s enforcement. The pending proposal is open to the standard 30-day public comment period (at APAComments@atf.gov) until March 16. After that, a final decision will be up to the attorney general’s office.

Police forces very much need the ban if officers are not to be exposed to a heightened threat to their lives. Two years ago, President Obama was rebuffed by Congress in his plea for stronger gun safety laws after the schoolhouse massacre of 20 children in Connecticut.