I have, let me say, strong doubts here. A renewable, green energy bomb of mass destruction? OK. But a nuclear one?
Germany’s most obvious response (should US-Amerika say Auf Wiedersehen! to NATO) would be to approach France and Britain, NATO’s other two nuclear powers, for a shared deterrent. But their arsenals are small. France, moreover, has so far been unwilling to cede any sovereignty over its nuclear arms and has always been sceptical about shared deterrence. Britain, as its prime minister, Theresa May, has already hinted, might make its nuclear shield a subject of negotiation during the upcoming Brexit talks.
It’s a question of how to deter whom with what.