Too bad the framers of the constitution didn't think of that one. We could start a war every once in a while to assure enough future presidents.
Also remember our military isn't exactly over flowing with children born with a silver spoon in the mouths. When we had a draft, a lot of parents tried to keep their kids out of the service. Some families had the wealth, contacts, and influence to make it happen. Those parents were both Dems and Reps. There are also individuals that accepted the call to arms and they too, come from both sides of the isle.
The all volunteer military isn't exactly swimming in wealth and priveledge. LHow many of those soldiers you see look like they skipped Harvard to sleep in the sand?