I would argue that even voluntary service is just (or can be) as stressful as involuntary service. Many people join the military for the benefits or out of a sense of duty. You may find that sense of duty misplaced, but regardless of the reasons I'm guessing most young men don't join the military to become murderers and witness their friends getting torn apart. So yes, even voluntary servicemen must make light of the hell they're living in.
EDIT: Just realized my comment kind of comes off as argumentative but I think we're in agreement on this one judging by your other comment.
Most likely because of the draft in place during the Vietnam war for American soldiers and the necessity for military service among young Vietnamese men defending their homeland.
Could be the case, but they seem to be downplaying the content and the last sentence reeks of attitude. I just think it's rather unnecessary. I could obviously be misinterpreting the comment but it seems rather clear to me.
Yes that is what the article is about, but I'm confused about your tone here. Do you have something more to say or do you prefer snark when commenting on things that don't interest you?
EDIT: Just realized my comment kind of comes off as argumentative but I think we're in agreement on this one judging by your other comment.