There isn’t any generally agreed-upon definition of “assault weapon,” but if we broadly mean the sort of firearms that are used in mass shootings — semiautomatic rifles and handguns with detachable magazines — then what Sorkin here is saying is the equivalent of, “You can sell cars, but not cars with automatic transmissions.” In many gun shops, semiautomatic rifles and handguns represent practically the entire inventory. I would be shocked if there were very many ordinary gun shops (as opposed to, say, fine-shotgun brokerages) in which the sale of semiautomatic rifles and handguns represented anything less than 75 percent of the firearms sold or 80 percent of the revenue. The AR-15 is the Toyota Camry of the firearm world.
In fact, the world of firearms outside of semiautomatic handguns and rifles is pretty small: There are a few revolver enthusiasts left in the world, and many big-game hunters still prefer bolt-action rifles. And fancy bird-hunters still prefer their side-by-side shotguns. But the vast majority of firearms for sale and in use — including by hunters and target shooters — are semiautomatic. All revolvers and shotguns combined (including semiautomatic shotguns) account for a very small share of firearms sales.