Is insisting folks join military alliances if they want to survive in a world where "second strikes only" seems to be the new normal for nuclear deterrence fail

Is insisting folks join military alliances if they want to survive in a world where "second strikes only" seems to be the new normal for nuclear deterrence failing? (I'm only being half sarcastic, since OTOH the Budapest agreement was pretty clear, but unless you wanna go full 1984 and have World War 1: Part Two, Electric Boogaloo with massive deaths by conventional weapons on both sides I don't have a good solution to issues like the current Ukraine crisis.)