"No nation wants or needs Nuclear Weapons except to deter enemy governments from attacking."

There may have been a time when that was true, but I doubt it's true anymore. During the Cold War, the Soviets were corrupt but rational and could always be relied upon to act in their own best interests. But do you really believe that Iran only seeks nukes for self-defense? These are apocalypse-minded fanatics who think it is their divinely mandated mission to wipe Israel off the face of the Earth. There is little doubt that if they are allowed to fully develop nuclear capability, they'll use it offensively.

North Korea is a whole different kettle of fish. That regime is irrational and unpredictable. Come to think of it, so is the current U.S. president. That's a recipe for disaster.