"The 2nd amendment doesn't mean just anyone can have guns, only that the National Guard can."

The 2nd amendment says, in full:

"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."

The Militia means every citizen. If you are a citizen, that means you. The authors of the bill of rights specifically recognized our right as citizens to bear arms as not infringeable. They didn't do that in order to protect shooting sports or so you'd have effective self-defense in the face of an armed assailant. Both of these are valuable in themselves. But the framers wrote the 2nd amendment to keep the federal government honest and answerable to the citizenry-to keep the state both secure and free.