The Smoking Gun Will Be a Mushroom Cloud

A Response to Gregory M. Reichberg in Today's National Catholic Reporter

Twenty years ago I was at work on a book that never got published. I was intrigued by the problem that George W. Bush had described unusually well, omitting his customary Malaprop logopathy. (The credit probably belongs to David Frum.) He told a Cincinnati audience, “Facing clear evidence of peril, we cannot wait for the final proof, the smoking gun that could come in the form of a mushroom cloud.” The image should seize us. But the peril does not only lie in the possibility of surprise attack.

The 2003 U.S. invasion of Iraq was not only one of the most egregious foreign policy blunders in the history of national states, but it also was grossly immoral. The fear that motivated it however, was rational and national states need to take that fear seriously in the twenty-first century. The fear, quite simply, is that waiting for an attack is before responding will not always be the right choice. Warfare has changed. The calculations of justness must also change. But how can we know when a preventive attack is justified to distinguish it from when it is not justified? The 2003-2011 war in Iraq stands as a stark caution while we embark on a question now with us again since the U.S. attack on Iran.

Having grown up during the Cold War and having come to political maturity in early Reagan years when duck-and-cover drills returned briefly to the classrooms within Chicago’s blast radius, I can recite the facts of a nuclear first strike from memory. From launch to impact, there are between 23-28 minutes to make a decision whether to retaliate. The only variable is the difference between land-based ICBM’s and where submarines fitted with SLBM’s might launch from. In either case, all constitutional hopes for a congressionally-declared war dissolve. There will be no public conversation because the public probably won’t even know until the blasts incinerate our cities. The decision to retaliate will rest with one person alone because it must. The battle is over before the bombs detonate. We have lost the moment we have discovered we are at war.

The weeks and months after the September 11th, 2001 attacks offered us a similar education. The threat is not confined to ICBM’s or SLBM’s. We face suitcase bombs and dirty bombs and biological weapons and chemical weapons, all of which might be deployed against an urban population by just one attacker. More recently, the war in Ukraine has taught us that swarms of commercially-available drones can accomplish what suicide bombers can do—without the suicide. In the twenty-first century, war can be both precisely-targeted and devastatingly deadly to large civilian populations. War does not look the way it looked in the time of Hugo Grotius or Thomas Aquinas or Augustine of Hippo. So, how do we defend innocent human life justly in this situation? That was the question that animated my abortive book twenty years ago.

And of course, the answer lies in prevention. The best sort of prevention is the kind of prevention that keeps states who do not already possess weapons of mass destruction from getting them. The 2018 nuclear deal with Iran was an important sort of just prevention. The non-proliferation treaty regime is an even better kind of prevention. Best of all is the prevention that pursues just relations and trust between nations so that peace is preserved and war is not contemplated.

But those are not always options we have. Sometimes we do have to contemplate the military intervention that might be required to prevent a devastating, mass attack that can come without warning. We do not have the luxury of the ancient world or the medieval world, when it took weeks or months to mass forces for an attack, and armies or navies generally met for battle far away from civilian centers. In those days, there was a long time for diplomacy, there was a long time for readiness, and there was considerably less risk to innocent noncombatants. The situation has changed. Consider, for example, how quickly U.S. bombers flew from Missouri to Iran without warning. War comes swiftly in the twenty-first century. Our calculations about justness now need to contemplate preventive war, and the way to approach preventive war justly. I think this is undeniable.

I also think it is risky, and as I’ve said the 2003-2011 war in Iraq is the instructive example. So the question is—How can we contemplate preventive self-defense in a climate where we lack perfect knowledge about whether an attack in fact is imminent? How can preventive war not become what it became for George W. Bush—a license to attack in the absence of an actually symmetrical threat? But my abandoned book did offer an answer.

A preventive war might be just when (and, only when) the community of nations is satisfied that a threshold has been met, the threat of imminent attack appears credible and substantial. To make preventive war justly, a state must entrust part of its sovereignty to the judgments of other nations. A nation must ask other nations, and accept the consensus of their judgments. To put it differently—when a nation cannot persuade allied nations that a threat is credible and substantial, the threat probably is not credible and substantial.

This is not an approach that would have seemed prudent or possible in the ancient and medieval worlds. In those days, the networks of established and ongoing alliances and affiliations among states (the UN, NATO, the OECD, the OAS, and onward the list goes) did not exist. But the global community of the twenty-first century depends on these relationships for security and prosperity every day. Those relationships can be trusted here, too. If the United States cannot convince its NATO allies or regional partners that a preventive attack is needed, why should anyone think a preventive attack is needed?

The U.S. failed to achieve that consensus in the 2003 invasion of Iraq, and we were wrong. The U.S. failed to achieve that consensus in the 2025 bombing of Iran, and we were wrong. The U.S. did achieve that consensus in the 1991 defense of Kuwait, and we were right.¹

The right answer to the dangerous question of preventive warfare is that nations need one another. Allies must trust each other, and shape their decisions around alliances and relationships they already have learned to trust with nations that share complex interdependencies with them already.

Sometimes, a nation could need to engage in preventive warfare. We live in a time when the smoking gun can be a mushroom cloud. A preventive war might be just. But, as much as anywhere else in political life, working together collaboratively to muddle through these difficult challenges is the only hope we have to see our way through to peace and justice.

1. The example of the 1991 action for Kuwait was not an example of preventive war. It was, however, an instructive example of how a consensus among allies makes a better judgment about whether war is needed and about how success in war is defined.