Ukraine

I've seen an interview with a former CIA spy who used to work in the bunker where they would have to insert rings (two of them) if an order came that said to launch nukes. They preselected them all on a psychological profile and, importantly, they did drills that they didn't know were drills. So they never knew whether the command coming in was real or not. They "launched" every single time.

I can very well imagine that this kind of "loyalty" would be tested in Russia as well.