The question to ask is what is the purpose of the right to bear arms? Why did the founders find it so important to protect this right? Was it so individuals can hunt? Was it so people can have fun playing with their guns? The purpose was to defend themselves from a tyrannical government, not just from criminals. The 2nd amendment is a natural right for individuals to defend themselves with weaponry that could be used by those from whom they need protection. The government has an insane amount of firepower. In turn, the private citizenry has a right to much of the same firepower. Assault rifles, I would argue, are the common weapons of use by soldiers and as such citizens must protect their right to own them.