It was simply something that I wanted to do. Not joining would not be true to myself.
A friend and I were having a discussion about the merits of the war. He was antiwar, and I was not opposed to it. During the discussion he asked me "Why don't you join up then?"
I didn't have an excuse. Either I need to change my political beliefs, I am a coward and a hypocrite, or I should join. I joined.
My political beliefs have since changed. I am much closer to a libertarian now than I was before. I still am not antiwar, sometimes violence is the answer.
I learned firsthand the meaning of "It was the best of times. It was the worst of times."