To make my story short, my lottery number was never called. Thus, I did not serve. However, I had other experiences regarding the Vietnam War era, which I will pass on for what they are worth.
In the fall 1965, I lived in a graduate dorm at UNC-CH. I remember the Selective Service calling up "non-critical" major grad students, such History and Economics majors during the semester. Such grad students moved out of the dorm during October / November 1965, presumably to report to a military service. I majored in Computer Science, which was deemed by the powers-that-be a "critical" major.
Three weeks before I was to be married in June 1966, my mother called me on the phone and said "you have a letter here from the Selective Service Board. Do you want me to open it?" I said "yes". The letter read that I was to appear at Fort Ford in Detroit on a date very near the day I was to be married. I was "cleared" to serve. So I asked my major professor at UNC-CH to write a letter to the Selective Service Board in my home town that I was under contract to teach "Data Procerssing" at a community college in Michigan after my marriage. The short of this was that I received a "Critical Skills" deferment for the academic year 1966-67 and subsequently for academic years 1967-68 and 1968-69 at UNC-CH.
While at UNC-Ch in 1967 or 1968, I remember a violent protest against the Vietnam War. Basically, one of the cafeterias at UNC-Ch was pretty badly affected as a side-effect of the protest.
The above is the extent of my Vietnam Era related personal experiences and recollections. In retrospect, I believe that we lost 56000+ men for no good reason. The Domino Theory of Communism simply was a myth that the government exploited.