Yes, assault rifles are legal to own in the United States. The United States has some of the loosest gun laws in the world. Therefore, there are lots of types of weapons you can own in the United States, and an assault rifle is definitely one of them. At the same time, assault rifles have not always been legal in the United States.
In 1994, Congress passed the Violent Crime Control and Law Enforcement Act which made it basically illegal to manufacture or possess a semiautomatic assault weapon. For several years during the 1990s and early 2000s, this assault weapon ban was in place in the United States. The ban was allowed to expire in 2004 without being renewed, and assault rifles once again became legal in the United States. At the same time, if you are interested in owning an assault rifle, you need to take a look at the laws of your state.
The vast majority of states allow assault rifles. States do not have to explicitly allow assault rifles by codifying them into law, but they simply need to not have legislation against them. Because the overwhelming majority of states allow assault rifles to be purchased within their borders, it is easier to name the states that do not allow assault rifles.
There are several states that have a ban on assault weapons. They are California, Connecticut, Delaware, New York, New Jersey, Hawaii, Massachusetts, and Maryland. In addition, the District of Columbia also has an assault weapon ban within its borders. Each of these states has its own rules concerning the registration of already-owned assault weapons, transportation of weapons, and the firearms that are defined as assault weapons. For example, while Hawaii has an assault weapons ban, but it only applies to assault pistols.
People argue that it is their right under the Constitution to purchase an assault rifle, and some people believe they need them for self-defense. Those opposed to assault rifle ownership argue that the people who wrote the Constitution never could have envisioned that assault rifles would be invented, and they believe the Constitution should be adjusted to reflect the reality of the danger posed by assault weapons, particularly when in the hands of civilians.
Yes, the AR-15 is considered an assault rifle, one of the most common assault rifles people purchase. The AR-15 has a similar build and look to certain military weapons, but there are distinctive features that differentiate the two. The main distinction would be the semi-automatic nature of the AR-15. Semi-automatic weapons only fire one round per trigger pull, versus a fully automatic assault rifle that can fire multiple. In addition, the abbreviation "AR" in the name does not stand for Assault Rifle. AR is short for ArmaLite, a name referring to the manufacturer of the gun in the 1950s.