[Svartalfiar]

maybe they were drafted and only stayed as long they had do, and did not reenlist?

Yea, that's probably it. Looking closer at my list, it's almost all 60s/VietNam. Seems odd it would only be a two year term though, I would think it would be a three or four year at minimum.

[Kaslin]

My husband served two tours in Vietnam 1967-68 and 1971 for which he both volunteered. He was never drafted, he enlisted in 1954. He did his first overseas tour in S.Korea, right after the war.