How can an argument be made that an arms build-up-might lead to peace

Sort of like the Cold War- the concept of MAD (mutually assured destruction) where both countries built up their arsenal of nuclear weapons to where if one attacked the other, the attacked could basically destroy the attacker with the stockpile of missiles it had. This stalemate resulted in no fighting due to the fear of what would happen if a nuclear war was fought. So in essence, this is peace by means of arms stockpiling.

Hope that helps.