Damn, who are you, a Canadian? Did you fail your high school government class? It is like you did not even ever read the Constitution, or grow up in this nation.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.[32]"
en.wikipedia.org
"The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.[6]"
en.wikipedia.org