Incidentally, a college-educated but reluctant son or daughter from a rich family might not be any worse than some poor 40-year old guy who barely has a high school diploma who joins the Army because his daughter is dying from leukemia and that's the only way he can get medical care for her.

There are LOTS of people in our military now who are there because their other alternatives were just plain worse. Is that what makes a professional soldier, someone who joins simply because the alternatives are unbearable? If that's true, then a draft would not affect that at all: you'd have people joining to stay out of prison, rather than to avoid becoming homeless or whatever. Basically the same thing: join or suffer. The only real difference with a draft is, the wealthy get the same choices as the poor.