There are millions of assault weapons in America. The AR-15 is the most popular rifle in the nation. There are tens of millions of high-capacity magazines, and they’re extraordinarily easy to make. Both are unquestionably in “common use.”
This means that the foreseeable criminal threat to you or your family comes from a person wielding — at the very least — a semiautomatic pistol with a high-capacity magazine. This is one reason that police typically don’t carry revolvers. Their own weapons of choice have evolved to deal with the threat, and — as my colleague Charlie Cooke is fond of noting — if a person doesn’t “need” a high-capacity magazine to defend himself, then why do the police use them?
If I use an AR-15 for home defense, then I possess firepower that matches or likely exceeds (given how rarely rifles are used in gun crimes) that of any likely home intruder. Limit the size of the magazine to, say, ten rounds, and you’ve placed the law-abiding homeowner at a disadvantage. Prohibit them from obtaining a compact, easy-to-use, highly accurate carbine, and you’ve ensured that homeowners will be defending themselves with less accurate weapons. The best weapons “in common use” would be reserved for criminals.
Moreover, an assault-weapon ban (along with a ban on high-capacity magazines) would gut the concept of an armed citizenry as a final, emergency bulwark against tyranny. No credible person doubts that the combination of a reliable semiautomatic rifle and a large-capacity magazine is far more potent than a revolver, bolt-action rifle, or pump-action shotgun. A free citizen armed with an assault rifle is more formidable than a free citizen armed only with a pistol. A population armed with assault rifles is more formidable than a population armed with less lethal weapons.
The argument is not that a collection of random citizens should be able to go head-to-head with the Third Cavalry Regiment. That’s absurd. Nor is the argument that citizens should possess weapons “in common use” in the military. Rather, for the Second Amendment to remain a meaningful check on state power, citizens must be able to possess the kinds and categories of weapons that can at least deter state overreach, that would make true authoritarianism too costly to attempt.