Even if enacted, Feinstein’s proposal would be the most likely of all the major gun reforms being considered in Washington today to be overturned on Second Amendment grounds. The Supreme Court has held that the Second Amendment protects arms that are “in common use” for lawful purposes, like self-defense. There seems little doubt that assault weapons are in common use, given the millions of them in circulation. Of course, the courts might still have upheld the ban; a federal appeals court recently said that outlawing this one category of firearm didn’t substantially interfere with anyone’s self-defense. Strangely, the best thing an assault-weapons ban would have going for it is its loopholes. Because you could buy the exact same gun without the pistol grip, you weren’t really denied the right to have a semiautomatic rifle to defend yourself.

There was one certain impact of proposing to ban the sale of assault weapons: it was guaranteed to stir gun-rights proponents to action. Ever since Obama was elected, they’ve been claiming that he wanted to ban guns. Gun-control advocates mocked this claim—then proposed to ban a gun. Not only that, the gun they were trying to ban happened to be the most popular rifle in America. It’s one thing to ban machine guns, which few law-abiding people ever wanted or used. It’s another thing entirely to ban a gun that millions of American gun enthusiasts love to shoot.

Ironically, the people who may be saddest to see Feinstein’s proposal go down are the gun-rights hardliners. They knew all along that the ban was riddled with loopholes, was easy to evade, and had little potential to impact crime. That’s in part why they wanted to focus on this proposal, rather than on background checks or limits on high-capacity magazines.