Bruce G. Blair is a nuclear security expert and a research scholar at the Program on Science and Global Security at Princeton and the co-founder of Global Zero.



Among the novel notions that have tumbled casually from Donald Trump’s mouth in recent months is this rather unnerving observation about nuclear weapons: “If we have them, why can’t we use them?” he reportedly said. At another point Trump declared: "Somebody hits us within ISIS, you wouldn’t fight back with a nuke?" He was excoriated by the experts, of course—including by a former Minuteman missile launch officer who wrote in The Los Angeles Times that although he was a lifelong Republican he was terrified that Trump might become president. I myself (a former Minuteman launch officer as well) have warned that in an era when decision-making has been reduced to seconds the president has virtually unlimited powers to fire off nuclear weapons—there is no advice-and-consent by the Senate, no constitutional constraints or other real check—and a President Trump “would be free to launch a civilization-ending nuclear war on his own any time he chose.”

Despite those fears, the truth is that Trump—at least while he’s not yet president—has actually launched a healthy debate about nuclear weapons today. He is right to question the pat and haughty conventional wisdom of the pundits, which boils down to the notion that of course nuclear weapons serve only to deter aggression against the United States and our allies. How dumb can you be to not know that deterrence is their only purpose and that any plans for their actual use are simply meant to bolster the credibility of deterrence?


“It’s the deterrent effect, stupid” is such a naive and simplistic view that one hardly knows where to weigh in. Perhaps the best starting point to enrich the debate is to ask the question what role nuclear weapons serve if deterrence fails. You would not know it from the criticism of Trump, but there is no guarantee that deterrence will not fail someday. Deterrence is a psychological construct that requires us to enter the unknowable minds of any number of leaders including the likes of Kim Jong Un (North Korea), Vladimir Putin (Russia), Xi Jinping (China) and India’s Narendra Modi (who, by the way, just like Obama has a nuclear briefcase and the codes and communications links to expedite the authorization of the use of India’s nuclear forces), and oh yeah, that guy who runs Pakistan. It’s Nawaz Sharif, but the Pakistani Army runs the nuclear show—who are we dealing with there?

If you want to doubt Trump’s state of mind, why not that guy who runs North Korea? What does anyone really know he will do in the heat of passion and conflict with his neighbors and the United States? Think you can read Putin’s mind? Think again. Russia has in place plans to use nukes first and early in a conflict.

And deterrence could fail as a result of accidents, unauthorized actions, misreading of enemy intent, and launch on false warning (mistakenly believing that deterrence has failed and enemy warheads are incoming when in reality this belief stems from faulty intelligence, glitches in early warning satellites and ground radars, human error, communications failures, cyber corruption of early warning data, etc.).

And as it turns out, just as Trump has suggested, our nuclear plans in fact do envision the actual use of nuclear weapons in a wide range of situations including scenarios in which deterrence has already failed or is expected to fail imminently. U.S. nuclear war plans exist to decisively defeat North Korea in wartime. They exist to preemptively strike a Russia or China if these nations appear to be executing their nuclear war-fighting options. They exist to retaliate to enemy strikes in a way that allows for the enemy to conclude that it is preferable to end or suspend its attack before further escalation occurs. Nuclear employment guidance since the beginning of the nuclear age have called for “firebreaks” of sorts to be established that allows a nuclear exchange to be terminated on terms that are favorable to the United States. Language along these lines certainly would be found in President Obama’s nuclear employment guidance.

The current secretary of defense, Ash Carter, says openly that “winning” is the goal of war, including nuclear war. That would be infinitely easier in operational military terms if the enemy is a country like Iran, which does not possess nuclear weapons. Why then do we have nuclear attack plans ready for rapid execution to take down Iran? Why did we have them in place, until recently, to strike Syria, Libya and Iraq? We would be using them first against these nations; is that deterrence?

Do we need to destroy nearly 1,000 aimpoints in Russia and over 400 aimpoints in China in order to “deter” these nations, or could we project a powerful threat with far fewer numbers? What is the excess for? Why do we aim most of our weapons at the opposing nuclear forces if our goal is simply to deter? Might it possibly be to try to prevail if deterrence gets wobbly or crumbles? Why hasn’t our nuclear priesthood settled for the ability to destroy every major city in Russia and China as the bedrock of deterrence. Why do they demand far more?

To glibly invoke deterrence in response to these points is to expose naivety and lack of historical understanding about the past and current nuclear posture of the United States, and our adversaries. You would never learn anything about how U.S. nuclear strategy evolved over the past decades if you were content to accept that deterrence explains everything about this evolution. You would never know that President Reagan directed his nuclear establishment to prepare a war plan that would ensure that U.S. strategic forces and their nuclear commanders could fight a nuclear war for at least six months, and prevail in the end. You would never really grasp the reasoning behind the long-standing U.S. position that allows for the first use of nuclear weapons in a crisis or conflict. If deterrence suffices to explain everything, then I guess I can blithely discard whole shelves of books devoted to the subject.

Donald Trump has done the nation a favor by raising a host of legitimate and important questions about the role and purpose of America’s very large arsenal of more than 4,000 nuclear weapons in operation or reserve. He himself lacks the expertise to answer them but his ignorance is hardly greater than most of his critics. Would that the latter open their own minds, show some curiosity, do their homework, and then add a dollop of intelligent insight into the debate. A healthy national conversation and debate over the deterrence question are long overdue.