One thing I haven't seen brought up yet as part of the theory is his/her role as an international figure. How would this affect the president's negotiating credibilty with nations that are on either end of the gun rights spectrum. I would assume that the laws of the host country would apply but then again, the president does travel with small army as has been pointed out. Therefore, there is clearly a way to bypass the laws of the common man.
All in all, this is a facinating discussion.
91/30 Mosin Nagant, P95 Ruger
M&P S&W .38, Savage 111 30.06
Springfield XD .45