The second amendment may have originally been intended to protect the population from the federal government, but subsequent advances in weapons technology and military tactics have rendered that protection completely ineffective. At the same time, these advances make it possible for even a single person to inflict incredible harm on a population, harm far beyond what the writers of the constitution could have imagined.

The argument therefore is that widespread possession of particularly dangerous weapons by the general population has no benefit and substantial drawbacks.

Nobody is seriously considering banning ownership of rifles, but it's worth discussing how more stringent requirements on training, registration, and storage could reduce the number of deaths by firearm.