Many of my libertarian friends like to cite Thomas Jefferson’s intemperate remarks on gun ownership, suggesting that the original intent was to preserve the right of violent revolution.
May I suggest a more patriotic view: the Second Amendment was written to prevent ever having a need for violent revolution in the first place. The Second Amendment was written to eliminate the need for such abominations as the USA PATRIOT Act. With civilian gun ownership and training the norm, there are no soft targets for terrorists to attack.
See my latest addition to my series on Winning the War on Terror: The Original Anti Terrorism Act.