Rush would have been 18 in 1969.....the year the draft lottery began. The others you mentioned would have been 23 or older in 1965 when the Nam draft began.....not likely candidates. I agree that Kerrey did his war effort and to my knowledge served well. And frequently this is a plus. Unfortunately, whatever wisdom he acquired from that honourable service has not translated to his politics....in my view.
That is just stupid. First of all, not everyone was called. Of those that were called, not all were eligible. Lack of service does not a draft doger make.
Serving in the military is an honorable vocation, but there are other honorable ways to spend your time too. Not serving (because of medical or other reasons) is not akin to leading demonstrations in England or trotting around Russia in lieu of serving.
Back then there was a draft. Almost everyone who served was drafted, or in your words, "forced" to serve. Fine Americans all. As were the many who didn't serve in the military during that time. My husband, who had two Viet Nam tours, doesn't understand the anger some people still feel toward those who weren't drafted/forced, or didn't volunteer.