In the grand scheme of things, the situation that held during the Cold War was a historical accident. Not every nuclear bomb in the future will necessarily be possessed by nations who are facing adversaries who can respond in kind to the use of nuclear weapons. Nuclear weapons are very scary indeed, and we are very lucky to have made it decades since they have last been used in war. I have good faith that we will make it to a century, but I would not make a bet that they will never, ever be used in anger ever again.