[of]

This is a good point - why has everyone downvoted it?

[sillysaurus3]

17 year old Marines are some of the most efficient killing machines on the planet. It's why we used them in WW2. Brown was 18.

Youth alone isn't relevant. For example, http://en.wikipedia.org/wiki/Jacklyn_H._Lucas#Marine_Corps_s...

[of]

That's different, though. Michael Brown was not an "efficient killing machine" who signed up for the marines at age 17.