Mentioning previous answers is just a starting point, not to discourage more discussion. More questions, data, or debate is welcome.

There's a long and informative answer under "Why did Hitler not invade Switzerland?" at https://www.reddit.com/r/AskHistorians/comments/4rciqp/why_did_hitler_not_invade_switzerland/d4zyeul/ by /u/Georgy_K_Zhukov^(not an actual Minister of Defence of the Union of Soviet Socialist Republics).