Gun control age restrictions on assault weapons

Mass shootings in schools keep occurring over and over in this country and is being committed by teenagers that can purchase an assault which is deadlier than a hand gun which they cannot purchase until the age of 21. If a person isn't serving honorably in the military they shouldn't be allowed to purchase this type of weapon until the age 21. It's no difference between the age restrictions for alcohol. If a child or teen is using a gun of any kind it should always be under parental control. Most young individuals aren't ready for the responsibility of owning a weapon because they have fully comprehended the meaning of life.