Couple of things to consider here, some of which have been mentioned previously...
- The POTUS could indeed sign an E/O authorizing himself to carry.
- The POTUS could use his/her significant political weight to influence, both openly and behind closed doors, the reversal of draconian gun laws in certain locations of the U.S.
- The POTUS does not need to carry. Yes, there's tons of SS agents around the POTUS at all times... Yes, they are well-armed and even better trained. However, since when does the need to carry determine anything for us?
- Normally, most of us advocate that anyone who wants to carry, should, after obtaining proper training and permits (if permitting is required). Well, the POTUS can create a "permit" for himself via E/O... Therefore, if the POTUS wants to carry, he should.
It would be a real political statement regarding firearms use in the country. Sure, the POTUS doesn't need to... But why shouldn't he/she? The POTUS is just as much a citizen as you or I...
"To preserve liberty, it is essential that the whole body of the people always possess arms, and be taught alike, especially when young, how to use them." -Richard Henry Lee, Virginia delegate to the Continental Congress, initiator of the Declaration of Independence, and member of the first Senate, which passed the Bill of Rights.