Alien to most Americans too. Let’s break it down.

• Pedantry first: the garden variety AR-15 is not an “assault rifle”. (AR stands for “Armalite” – the company that first developed the rifle, not “assault rifle”.) Assault Rifle is a technical term with a technical definition: a shoulder-fired rifle in intermediate caliber with select fire. The AR-15s you usually see meet all those criteria except for the select fire: since they’re not capable of fully automatic fire, they’re not assault rifles. (Which is why efforts to ban them are usually called “assault weapon” bans – “assault weapon” is a term with no officially accepted definition, so it can mean whatever the people trying to ban things want it to mean.) And for an even deeper level of pedantry: some people will mistakenly tell you something along the lines of “AR-15 is the semi-auto civilian version, while the full-auto military version is called a M-16 or M-4.” While that’s generally the case, it’s not really true. In the early days of adopting it, the US military adopted the AR-15 and designated it the M-16 for internal reference. But the company making them (Colt at that time) still called them AR-15s and (for a while) still marked military rifles as “AR-15”. Also, back in those early days, it was legal to sell newly made full-auto guns to civilians, and while it wasn’t very common, it did happen, so there are a few full-auto civilian AR-15s in existence, but most of that is just purely academic curiosities, really.

• While some states have barely any restrictions (basically just the federally mandated background check), many states do have significant restrictions. Since the states with restrictions are some of the most populated states, that actually affects the vast majority of Americans. It varies widely between states, but it’s common to have waiting periods, training requirements, or to even ban AR-15 style guns outright – the various ‘assault weapon’ bans, each one with its own slightly different definition of what an ‘assault weapon’ is. (And gun stores will refuse to sell to out-of-state buyers, so you can’t easily circumvent these bans by simply traveling to a different state.) Most Americans can’t simply walk into a gun store and buy an AR-15 ‘over the counter’. For some, it’s just not possible to buy one at all. For others, it can be a difficult process that may eventually conclude with a technically ‘over the counter’ sale, it’s definitely not the just ‘walk in and buy one’ kind of thing you’re talking about.