Getting into the NSA requires much more than a security clearance from the AF or Marine Corps Reserve. Secondly being a police officer doesn't qualify you to do anything beyond police work. It seems like you've built a plan here that isn't grounded in reality.
You need college (mathematics or some sort of tech degree), foreign languages, foreign travel (which you may get in the reserves) and a whole hosts of other things to be competitive for major agency work like the NSA. I've never met an NSA recruiter at drill, basic training or MEPS. They recruit from college campuses.
My advice, join the branch you want to join, don't let one recruiter screw that up, use the reserves to go to college, stay debt free, and make a run at the NSA, CIA, DIA, or even military intelligence. Hell, just go for intelligence as a reservist, enroll in college, and chase the NSA.
Be a jet pilot then try to be an airforce pj that would be awesome. I hardly know anything about the two well I know marines but they are very different.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.