Three times on Facebook this weekend, I saw the phrase “semi-automatic machine gun.” I don’t know where it’s coming from, but such a beast does not exist.

To explain:

• A semi-automatic gun fires one shot every time you pull the trigger.
• A “machine gun” (a fully-automatic firearm) fires multiple shots every time you press the trigger.

Fully-automatic guns have been strictly regulated in America since 1934, and are very difficult to buy. Because it is not legal for ordinary people to buy any fully-automatic gun that was made after 1987 1986, most of the working full-auto guns that are legal for ordinary people to own cost a lot of money ($10,000 or more). Military and law enforcement agencies can and do purchase new full-auto guns, but ordinary people cannot.

So when the media or politicians talk about banning “assault weapons,” they are not talking about banning guns that work like full-auto military weapons. Instead, these laws would ban simple, ordinary guns that have some cosmetic features that give them a military look — that’s all. It’s very confusing for people who don’t pay close attention to gun issues.