DoD I can understand, but certainly not in it's present form. That's an entirely different debate altogether.

DoD is essential to the safety of the country, which our government has an obligation to protect. Congress was tasked by the Constitution to provide for postal routes and build roads. Well, I think we can safely say this has been taken care of. Why, then, has the government allowed the USPS to morph much past it's original intent? I think it could be that the government itself has lost sight of it's original intent...
Besides, I can't legally carry a legally concealed firearm into one of their facilities...so tell me again why I should give them my business?
</fawked tangent>