A SPECTER is haunting Washington—the specter of nuclear war with North Korea. The idea that the Trump administration should endorse a military solution—and a full-blown war if necessary—to degrade or destroy North Korea’s nuclear-weapons program is acquiring a new prominence. Advocates of war argue that the time to hit North Korea is now. They say that time is running out, and that Pyongyang will soon perfect its ability to attack America. Their contention is that America can knock out North Korea’s nuclear program with some “shock and awe”–style bolt from the blue. Finally, they say that a war “over there” would be better than the death of innocent Americans “over here.”

Such thinking is redolent of the Iraq War. Just as the war in Iraq evaded the prediction that it would be a “cakewalk,” so a conflict over North Korea would likely issue in a calamity. There is no widespread public support, as a recent Washington Post–ABC News poll indicates, for a preemptive American strike on North Korea: 67 percent of Americans say Washington should act only if North Korea attacks it or our allies first. Before Washington experiences a fresh spasm of war fever on the Potomac, it’s imperative to examine just why a conflict with North Korea is inimical to America’s national interest. For the notion that America can “totally destroy” North Korea, as President Trump put it, with impunity is not quite persuasive. The result could even be a wider conflict, one that draws in great powers such as Russia and China that would seek to defend what they perceive as their own national interests.

Today, we live an age where America’s greatest strategic advantage—two big oceans that protect us from the great geopolitical struggles in Europe and Asia, both past and present—is no longer the strategic safety blanket it once was, thanks to modern missile technology. Put simply, while the American military is the most destructive force ever devised in human history, such a force cannot guarantee that Washington will eliminate every single North Korean nuclear weapon. Nor can we ensure that if Pyongyang retaliates, potentially with whatever nuclear weapons we miss, that our missile defenses can keep us safe. Quite the contrary.

The truth is that a war with North Korea could be nothing like the First Gulf War, Yugoslavia, Kosovo, Afghanistan, the Second Gulf War or Libya. Such a conflict could be an epic struggle in which millions of people, on the Korean Peninsula, in Japan and even in the continental United States, could perish. The best path forward is to practice the foreign-policy doctrine that ended the Cold War peacefully: containment. Containment, rather than open conflict or outright appeasement, is not a panacea, but under the circumstances it is the best of the options that Washington can pursue. As during the Cold War, a patient and vigilant strategy can wait out a hostile regime in the expectation that it will eventually crumble. A look at the possible outcomes of a nuclear conflict shows why it is more prudent to adopt this approach than to strike first.

WHEN WE consider the possibility of a military operation against North Korea, it is helpful to take a step back and consider from Pyongyang’s perspective how it might respond. North Korean leader Kim Jong-un may not wish to counter such a strike by using the full range of his military options, fearing such an attack could unleash his worst fear: regime change.

This is where U.S. military planners begin to get nervous, as North Korea—even despite having an army that looks more like it was outfitted in the 1950s—has many ways to keep us guessing militarily. Kim could opt for less conventional means to instill fear and panic, attacking in an asymmetric manner that would be hard to counter.

For example, Kim could order an attack on South Korea’s vast civilian nuclear infrastructure, unleashing deadly plumes of radioactive fallout. Seoul operates twenty-four nuclear power plants that could all come under various forms of North Korean attack, though they are relatively far from the North. With many of these facilities lumped together, Pyongyang could fire a salvo of missiles at these plants, creating an immediate humanitarian crisis.

The North Koreans could also use their special forces. They could infiltrate the South from existing tunnels to launch terror attacks against such facilities. If North Korea were to destroy just a few reactors, a disaster eclipsing Chernobyl could occur, killing tens of thousands and leaving millions of acres of South Korea an uninhabitable wasteland for generations.

THE ABOVE example is just one of the most basic ways in which North Korea could respond asymmetrically. If we broaden our consideration of what a total war would look like, we find ourselves staring into the nuclear abyss.

Several years ago, I took part in a series of computer-based war games at a reputable think tank in Washington to examine what might happen if North Korea and America engaged in a nuclear conflict. Over the course of a few days, we simulated three scenarios to explore what a war with North Korea would look like, focusing on nuclear-weapons use, and conducting one full war per day in a fast-paced exercise.

The first of these exercises—a small nuclear war, if such a thing exists—imagined a conflict in coming decades, in which North Korea launches conventional weapons in a surprise attack on U.S. and allied forces on the Korean Peninsula, responding to reports that America is considering building up its military might in northeast Asia for a possible attack and regime-change operation.

Kim starts this Second Korean War with an artillery strike on Seoul while firing hundreds of small- and medium-range missiles on targets all over northeast Asia. U.S. and allied forces counterattack, focusing mostly on Kim’s weapons of mass destruction, wiping out what they think is all of them.

Allied forces then move their way up the Korean Peninsula. But Kim, even with his forces battered and bloody, hid four nuclear weapons deep underground. He makes the ultimate decision: to launch a nuclear strike on Seoul and Tokyo. While the allies go on to win the war, Kim’s nuclear attacks—with one warhead each making it past allied missile defenses, detonating in each city—result in over one million people dead and millions more wounded.

From here it gets even worse. As though the above wasn’t bad enough, we pressed forward into a second scenario that begins with North Korea starting a conflict using nuclear weapons in a sort of atomic Pearl Harbor. In this exercise, we assume that U.S. forces are building up in the Asia-Pacific in preparation for a possible regime-change invasion of the North, responding to a demand from the international community for Pyongyang to give up its nuclear weapons. Sound familiar?

But Kim Jong-un is no fool. He knows that once U.S. forces are in place, they will try to take out his weapons of mass destruction, first from the air and then moving across the thirty-eighth parallel. Kim takes a gamble, and decides that his only course of action is to strike first with his most powerful of weapons. Kim, in what thankfully was just a war game, launches nuclear attacks on Seoul, Pusan, Incheon, Tokyo, Sendai and Nagoya, with one nuclear weapon hitting each city. Over two million people perish in the atomic fire before Kim is defeated.

The last war game, however, was the most shocking of them all. We assumed a similar scenario, with allied forces preparing for a possible invasion, but this time Kim decides to launch a preemptive attack on the U.S. homeland—to take as many people to the grave with him as possible, a goal the North Koreans have declared in the past. In this last war game, North Korea attacks the cities in the second scenario with atomic weapons, but also launches successful nuclear strikes on Los Angeles, San Francisco, Seattle and Portland. We were shocked to discover that the combined body count, across Asia and America, came to over three million people—before America’s nuclear counterattack, which would add millions more. After North Korea retaliates with every weapon it has, launching more nuclear attacks along with chemical- and biological-weapons strikes, eight million people have lost their lives.

WHAT IS to be done? There are five potential pathways to mitigating the North Korea challenge. None involve a unilateral military strike; rather, they all embrace the idea that containing Pyongyang is our best and only option.

First, the Trump administration needs to be honest with itself and the problem it faces. There is no room for thinking we have more time to “stop” North Korea from getting nuclear weapons and long-range missiles, a line constantly repeated by experts across the political spectrum. The truth is that Pyongyang already has them.

Second, we need to embrace a financial-containment strategy—limiting the amount of illegal money going into Pyongyang’s atomic and missile programs—as the only way to slow and potentially halt any further advances of North Korea’s missile programs. We should insist that all nine UN Security Council resolutions are not only followed to the letter of international law, but strengthened every time North Korea tests another missile or nuclear weapon.