The popular wisdom during the Cold War was that the greatest threat for a nuclear weapons attack came from the Soviet Union and their client states and vice versa. Now that the Cold War has ended, the nature of the nuclear threat has shifted dramatically in my view from individual states to rogue terrorists and madman dictators with nothing to lose like perhaps North Korea because any man who lets his own people starve to death as he lives in an opulent palace in comfort. North Korea and notable others excepted, the era of state on state nuclear annihilation has largely passed. When the nuclear era began
in the shadows of World War II, the world stage was lined with men like Hitler and Stalin, who through mass campaigns of paranoia and racism sent thousands of people to their deaths. Men like Stalin and Hitler cared nothing about human beings seeing them as cogs in the respective machineries of Nazism and Communism respectively. These men where brutal, paranoid, lunatics who viewed murder as sport and would’ve thought nothing about using an atomic bomb against their own people, much less the United States.
I am happy to report that the era of madmen in the mold of Stalin and Hitler has largely dissipated as the few remaining madmen are increasingly isolated from the world of the civilized. The threat for localized barbarianism is still painfully likely in several countries spanning Africa and Asia, but the odds of such localized death becoming nuclear are slim. Today’s leader understands that any brandishing of the atomic bomb against his neighbors is a good recipe to have many sets of nuclear guns aimed directly at you. Leaders are far more rational and understand the consequences taking the nuclear war option would bring: mass destruction of your people, a loss of power for yourself and global catastrophe. Even though the world still has dictators and autocrats, these men crave power and understand that power ends if your people are all routed in a massive counter-strike. One has to weigh is the nuclear option worth the destruction of their people and their own rather comfortable livelihood.
When the Cold War peaked, two countries had nuclear weapons and it was easy to deter, now the nuclear club is small, but growing, and because of the alliance system, every country has a larger nuclear brother that would come to its’ aid, forcing a leader, presumably a man of strategy and tactics to consider the counter-attack. Many leaders decide that the calculus of rewards isn’t worth the brutal deterrence. Furthermore, states no longer hold an absolute monopoly over the nuclear option. Despite best efforts, nuclear material is made available on black markets, a lot of it from the former Soviet Union, where terrorists can in theory buy the material, place it with other radio-active material. They are the threat because today’s terrorist does not operate from a state as Al Qaeda with it’s global reach has shown. Furthermore, terrorists are this generations Hitler and Stalin because like their World War II brethren, they largely do not care who they kill and have a vision for the world that operates outside of reality.