Alas, demilitarization of the US would take a very, VERY long time; our defense budget isn't just R&D, we have a massive standing army. Plus, just because we demilitarize doesn't mean other potentially hostile nations would follow suit, and it would leave us almost totally defenseless. In short, it'd paint a huge target on our backs. We may not have as many enemies as people like Bill-O the Clown would have you believe, but we do have people that are none too friendly towards us and would enjoy being able to actually hit us.