I don't know about "fun". I don't just don't like bullies and Marines are just the guys to deal with them. In my case look closer at the dates. Vietnam, Reagan military build up, Falkland Islands, and the Gulf War. Afghanistan and Iraq are the first wars I've missed in my adult lifetime.
The problem with being good at something means people call on you when there are tough jobs. And the reward for successfully completing a tough job is a tougher job.