For 6 decades nuclear deterrent and mutually assured destruction have prevented the worlds powers from going at each other directly. As terrifying as the thought of nuclear weapons may be it is still far less terrorizing then the large scale conventional that so defined the first half of the twentieth century.

Combined the two world wars left almost 90,000,000 soldiers and civilians dead. Any way you stack it peace enforced through MAD is preferable to that. Sure it may not be perfect, but wars where casualties are measured in the thousands or even the tens of thousands is a hell of an improvement over measuring them in the millions. This is why I fear a world without nuke more then I fear a world with them.