nuclear war is inherently mutually assured destruction for the country threatening it, belarus is a smaller country right next to russia, if they send a nuke they country getting that nuke wil retaliate and as a result belarus is no more. Nuclear war threats are little more than intimadation games, no sane country is willing to risk getting btfoed themselves, and if they do, then that would be a natural consquence of their stupidity. truthfully I'd probably risk it to show that as leader I refused to be intimidated into bullshit. the may nuke cities all over the world, but the countries they nuked would retaliate with their nukes. the fact if they're threatening nukes, its mostly for intimadation and not really wanting to nuke, because again mutually assured destruction.