I don't see why civilians should have assault rifles.

There are a lot of people more expert than I am about assault weapons, but there seem to be a lot of statements around that are clearly wrong. As a young man I did competitive target shooting with a small caliber rifle, trap shooting and hunted with both rifle and shotgun. I owned rifles, a shotgun and a pistol (which I sold before my first foreign posting). While that is a long time ago, I do have some  experience.

Assault rifles were conceived as military weapons. They are not intended to arm aircraft. They are not artillery. They are not sidearms. Indeed, they are intended for use by foot soldiers who are supported by troops with other weapons. They are definitely not intended "to kill as many people as possible", but rather to be used against enemy soldiers during battle.)

Generally they are designed to be rugged, relatively simple to operate, relatively light and easy to carry, and accurate to a range of 1000 feet. These are characteristics that are also useful for civilian purposes such as hunting deer or other large game.

Assault rifles are designed to allow the rifleman to shoot at people. Other weapons are better suited for varmint hunting, target shooting or hunting large game.

Assault weapons are intended to take enemies out of action.  There are advantages in wounding an enemy badly enough to disable him while leaving him to require medical attention and hospitalization; a hunting rifle on the other hand should drop the game animal and minimize its suffering.

An assault rifle should be able to switch among fully automatic fire, burst fire or single shot fire. There would seem to be no advantage to burst or automatic fire for hunting nor for target shooting.

Target rifles tend to be rather heavy -- they are not carried long distances and are designed to be heavy to increases accuracy.

Assault rifles use intermediate ammunition as it is lighter to carry, has a lighter kick when fired (especially important for burst and fully automatic fire), and produces the kinds of wounds useful for military purposes. They use detachable magazines that support the burst and fully automatic fire; a magazine that can be quickly replaced when one is exhausted. Other kinds of ammunition are better for other purposes (e.g. small bore ammunition for varmint hunting, large caliber for big game). I found single shot rifles appropriate for both hunting and target shooting; double barreled shotguns seem adequate for hunting although I used a single barrel shotgun for both trap shooting and hunting.

Assault rifles might be sought by criminals who intend them to be used against people or at least to intimidate people. We clearly want to prohibit such use and be sure that they don't get into criminal hands. They also can be dangerous in the hands of regular people who would have accidents with them or misuse them due to lack of understanding of their capabilities and proper use.

I don't see any reason why assault weapons would be useful for the average American. They are designed for soldiers. There may be some applications of assault rifles for law enforcement or for people in other specific occupations, and should be limited to those applications.