The Riddle of the Gun : Sam Harris

http://www.samharris.org/blog/item/the-riddle-of-the-gun

In fact, it can be easily argued that original intent of the Second
Amendment had nothing to do with the right of self-defense—which
remains the ethical case to be made for owning a firearm. The
amendment seems to have been written to allow the states to check the
power of the federal government by maintaining their militias. Given
the changes that have occurred in our military, and even in our
politics, the idea that a few pistols and an AR 15 in every home
constitutes a necessary bulwark against totalitarianism is fairly
ridiculous. If you believe that the armed forces of the United States
might one day come for you—and you think your cache of small arms will
suffice to defend you if they do—I've got a black helicopter to sell
you.

---SPSmith