AMEN! The 2nd Amendment is about the defense of the country and the people's defense against tyranny. There is no restriction or caveat in it. WMD are the only type that can be reasonably prohibited to individuals, and that prohibition should be as an amendment to the Constitution!
Elaine Scarry wrote a longish University of Pennsylvania Law Review article on the Second Amendment, distribution of power in the Constitution, and original intent. She also addressed the subject of destructive weapons, and nuclear weapons were a special focus of her article, which argues that recent arrangements for their use, predicated on a need for quick and massive response, are anticonstitutional and politically unhealthy.
http://www.saf.org/LawReviews/Scarry1.html
It's worth noting that the first government to pursue WMD specifically was the Third Reich, for precisely the reasons Scarry thinks are bad, among which was their power to absolve (i.e., make absolute) the ruler of the Third Reich of any sort of social check on his actions. The chain of command to his V-weapon operational teams was very short and fast.