Basically conservatives say that the 2nd amendment permits everyone in the United States to bear arms, and that regulating the ownership of firearms would be unconstitutional.
But the 2nd amendments goes like this:
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.
Now, pay attention to the "well regulated" and "militia" part. If i am understanding this correctly, the 2nd amendment permits the establishing and maintaining of a regulated (as in controlled and trained) paramilitary force (militia), not everyone to own a firearm. In short, an organization like the National Guard, an organization that citizens can join and receive training.
Now i stress AGAIN that i am not anti gun ownership. This is simply a question out of curiosity.
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*amendment