My son will be on 10-days' leave from the Army for his best friend's wedding. As best man, should he be the one to plan the bachelor party?

I believe that traditionally, yes, the best man does, but don't quote me on it.

Traditionally yes, he should plan/pay for the bachelor party. However, I also think it is circumstantial. If your son cannot afford it, then he should get all of the groomsmen together, and all pitch in. When I got married, my husbands best man was his father, who was not into going out, so the rest of the groomsmen took care of it.

He should... but when I got married my husband's little brother was the best man, and he was only 14. So, the next person in line was the one who got it set up!