The biggest surprise was the feeling of being trapped. In the US military you volunteer for a period of years and once you sign up you are in for that long unle

The biggest surprise was the feeling of being trapped. In the US military you volunteer for a period of years and once you sign up you are in for that long unless you get kicked out (really bad and career limiting), get discharged for administrative reasons (unusual at least in my day), or die (see above). This only fully sinks in after a few days of basic training. My service was a while back during the second cold war, which was actually pretty peaceful for the US military. The wars in the Middle East have added whole new dimension that I cannot comment on from personal experience.