VRPdommy are you an American citizen?
Whether you like it or not (many do not) the 2nd Amendment guarantees a citizen's right to posses firearms -- the courts have made lots of precedence of this.
There is no constitutional right for ordinary civilians (not in the military (or state militia)) to possess certain weapons that can be used in warfare or mass killings.
Congress can legislate reasonable gun control laws that ARE constitutional, Presidents can sign the bills into law, and if constitutional, the courts will uphold the law.
That is the way it works -- politics aside.
Alcohol and Cigarettes kill a LOT more people than guns do. But in America you can self-destruct legally like everywhere in the world. The age restriction is only an attempt to allow *responsible* adults to use Alcohol and Cigarettes
