What's all this about assault rifles?

     Disclosure: When it comes to guns, I am neither an enthusiast nor an expert. That said, I aspire to Socratic wisdom in most subjects, which is to say that I try to learn enough to have a good idea of just how much there is I don't know. And in so doing, I often learn enough to recognize when someone else does not know what they're talking about.

     In the gun control debate, I am beginning to recognize a lot of that on both sides. I'm sympathetic to those gun enthusiasts who criticize gun control advocates for not knowing what they're talking about when they say they want to ban assault rifles and who seem to be concerned more with what the weapon looks like than how it works.
     The enthusiast may go on to cite that an assault rifle is defined as a select-fire rifle that fires an intermediate cartridge stored in a detachable magazine. Select-fire means you can switch between semi-automatic (the weapon fires one bullet per pull of the trigger) and automatic fire (it fires more than one bullet per trigger pull). And, since full-auto weapons are already largely restricted from civilian hands and the AR15 is normally only available in semi-automatic configurations, it's not even a true assault rifle and you dumb ignorant gun-grabbers don't even know what you're talking about so shut up.

     Well, that's true, as far as it goes. But the select-fire distinction isn't really quite as meaningful as that makes it sound, at least as far as assault rifles are concerned. And here's where I'm going to talk technically about guns without being an expert.
     Anti-gun people often like to say that assault rifles are designed to kill large numbers of people very quickly, but that's not quite true. They are designed to be effective combat weapons, which means they're meant to be used against similarly armed people who are also actively trying to shoot back. For combat, semi-automatic fire and a large magazine is essential. It just so happens that these properties also make them ridiculously efficient at killing lots of people who are not firing back.
     See, in just about any kind of combat, you have to commit yourself to an attack. While you're in the en garde position with a sword, for example, you are ready to strike, parry, advance, retreat, depending on what you need to do. But when you commit to an attack, say, a lunge, you move out of the ready position, and your options suddenly narrow for a time. That's why we train so often to recover from a lunge, so that we can quickly return to the en garde position; you're vulnerable mid-attack, or mid-parry, or mid anything other than a guard position.
     It's the same with firearms. When you're in a ready position, you can aim and fire at a target of opportunity, or duck for cover, or advance or retreat. When you commit to firing a shot, you lose these other options for as long as it takes for you to recover from the recoil and reload for the next shot. In the days of muskets and muzzle-loading cannon, this took quite some time, and in fact that's where the tradition of the gun salute comes from: by firing your gun into the air, you demonstrated peaceful intentions since your weapon was now unloaded.
     So just as fencers gain an advantage by being able to recover into the en garde position quickly, combatants with firearms need to be able to return to their ready position quickly after firing. This is what has driven so many advances in firearm technology over the years, from pre-measured paper packet of gunpowder to the Remington repeating rifle to the Colt revolver to the modern semi-automatic, where the gun automatically ejects a spent shell casing and chambers a new round after firing, so you are back in your ready-to-fire position a fraction of a second after pulling the trigger. And this is important because real firefights are not just blasting away at enemy targets; they involve cover and concealment, maneuvering for position, feints and withdrawals and all sorts of tactical stuff I don't know about, because remember that the enemy is also trying to shoot back. So the less time you spend reloading, the more time you are ready to act or react, and the more effective you'll be.

     Now, once you have a gun that reloads itself after firing, it's a ridiculously easy matter to make it fire again and again and again while the trigger is still held in the firing position, so fully-automatic machine-guns are a natural consequence of this development. Machine guns fire full auto, hosing down an area with a continuous stream of bullets. We think of the appalling slaughter of the early part of the First World War, where a single machine gun nest could mow down hundreds of soldiers at a time as they tried to charge. And not coincidentally, a weapon designed to efficiently stop a massed infantry charge is just as efficient against massed civilians in a shopping mall.
     Full auto is, to be sure, a terrifying thing, but it's actually not what makes an assault rifle effective. In fact, they tried having your basic infantry assault rifle be full auto for a while in Vietnam, but it turned out to be a really, really bad idea. It used up a ridiculous amount of ammunition (which is heavy to carry around and thus never available in unlimited quantities), and didn't actually kill more enemies. Sure, it has its uses, but that's why infantry squads have a dedicated light machinegunner. Today, the typical assault rifle's selector does not have a setting for full-auto; instead, it can be set to fire a burst of 3 rounds per pull of the trigger.
     Remember that the main value in a semi-automatic weapon in combat is that you spend more time in your ready position, and less time reloading between attacks (pulls of the trigger). The more bullets fired per attack, the fewer attacks you can make before you have to reload. So it's actually better, for the most part, not to be firing bursts all the time.

     So that's why I say that the distinction between the semi-automatic AR15 and the select-fire capability of a military assault rifle isn't really that significant. (I'm not absolutely clear on why military assault rifles even have a burst setting, though I imagine it's for when you're reasonably confident you're actually going to hit the target and want to make sure you do damage, while maybe semi-auto fire is more for covering fire, making the enemy keep his head down while your buddy moves to a better position, stuff like that.)
     They can both fire the same number of attacks in the same amount of time; on burst setting, the military weapon will make fewer attacks, but those attacks will probably do more damage with three bullets instead of just one. And when firing at unarmoured civilian targets, that's just overkill.

     So bickering about whether or not an AR15 is technically an "assault rifle" is an unimportant distraction from the question as to whether or not they should be restricted. Select-fire or just semi-automatic, the weapon was designed for battle. Not for hunting, not for target practice, not for home defence (the typical home defense scenario is not a prolonged firefight). Battle.
     I'm not going to argue here whether or not such weapons should be in private hands.  I've already made my position on gun control fairly clear in other posts, and we can argue in the comment threads there. But feel free to correct me if I've made factual errors in my discussion of weapons and tactics.