Army is defacto banned to work on anything involving nuclear energy or weapons for awhile now. Rumor is the government does not trust. Pretty interesting. USAF is well quite scary with how bad they manage our nukes..
USAF, or specifically SAC, put priority on nuking as many civilian areas in as short amount of time as possible. Safety was a distant concern in that mindset, and led to fun stuff like first generation PADs (which controlled arming process of the warhead) being commonly (iirc, up to 50%?) configured to accept all zeroes as arming code.
USN at the same time considered PADs to be undue slowdown in the same mission and had enough power to just not have them mounted, afaik.