One possibility is a so-called bloody nose strike, which would involve destroying a North Korean missile launch site (bloodying the regime’s nose, as it were) in order to demonstrate the United States’ resolve. Some have gone even further, calling for “air and missile strike[s] against all known DPRK nuclear test facilities and missile launching and support facilities” in the event of a North Korean atmospheric nuclear test over the Pacific Ocean.

The goal of a limited strike would be fairly straightforward: demonstrate to Pyongyang that it cannot continue conducting tests without risking a U.S. response. Crucially, proponents of such a strike assume that the United States’ own massive conventional and nuclear capabilities could deter North Korean Supreme Leader Kim Jong Un from retaliating, as such an escalation would risk his own destruction. Advocates for a limited strike also tend to argue that, by assuring Pyongyang that the United States does not seek regime change but will never accept a nuclear North Korea, Washington can convince Kim that negotiations are the only viable way forward.

It is unlikely, however, that a strike would work as planned. It would have no guarantee of successfully destroying North Korean capabilities, and Kim may well feel compelled to respond to even a limited attack. Any strike would thus risk igniting a full-blown war on the Korean Peninsula that would endanger millions of lives and ultimately diminish U.S. power and influence in the Asia-Pacific.

RISKY BUSINESS

A successful preventive strike would likely require surprise. If Pyongyang became convinced that a U.S. strike was imminent, it might see itself in a “use or lose” situation and attack before the United States has a chance to take out its weapons—in effect preempting the prevention. Any strike would risk igniting a full-blown war on the Korean Peninsula that would endanger millions of lives.

Yet achieving surprise will be difficult. Washington would likely seek to work with Seoul and Tokyo to prepare their militaries for a potential North Korean response, which would involve moving troops and other resources into the region. South Korea and Japan would also want to ready their citizens to give them a better chance at survival in the event of a war. Finally, the United States might wish to evacuate the dependents of U.S. military personnel (of whom there are over 10,000) out of South Korea prior to a strike. These are very large operations that would be all but impossible for North Korea to miss.

Washington could forgo these preparations in order to preserve the element of surprise. Yet considering that there are between 100,000 and 500,000 U.S. citizens in South Korea (and several hundred thousand more in Japan) at any given time, this would put a very large number of American lives in danger. Moreover, conducting a surprise attack without providing South Korea and Japan adequate time to prepare could be deeply damaging to these critical U.S. alliances.

Another key aspect of any limited strike strategy would be to limit North Korean retaliation. Washington would have to convince Kim that, despite attacking his nuclear and missile infrastructure, it does not seek regime change. Yet North Korea is unlikely to take the United States at its word. For decades, a core element of North Korean state ideology has been that the United States is determined to invade and that nuclear weapons are necessary to prevent it. In fact, Kim said as much during his 2018 New Year’s address: “Even though the United States is wielding the nuclear stick and going wild for another war, it will not dare to invade us because we currently have a powerful nuclear deterrent.”

To avoid retaliation, Washington would have to convince Pyongyang that U.S. objectives are limited and that it does not seek regime change or intend to invade. This despite the fact that, in the event of a preventive strike, the United States would have just killed hundreds if not thousands of North Koreans in an attempt to remove what Pyongyang sees as its only guarantee against an invasion. Consider, too, how closely the nuclear program is tied to the legitimacy of Kim and his regime. Nuclear weapons are not only strategically important but fundamental to how the regime justifies its rule. From Pyongyang’s perspective, attacking North Korea’s nuclear weapons and missiles but sparing its leadership may be a distinction without a difference.

Even if Pyongyang accepts U.S. assurances, it may choose to retaliate anyway. Kim may believe that retaliation would be necessary to preserve deterrence in the future, out of fear that failing to respond to a major strike would tell Washington that it can attack North Korea at will. In fact, research suggests that weaker states often feel the need to attack stronger states in order to demonstrate strength and resolve and to deter possible future attacks.

HIGH COSTS, UNCERTAIN SUCCESS

Even if the United States was able to carry out the strikes and prevent a massive North Korean response, however, it might not be able to successfully destroy all of Kim’s nuclear weapons and missiles. Indeed, the Pentagon recently told Congress that eliminating all of North Korea’s nuclear weapons would require a ground invasion, probably owing to Pyongyang’s penchant for building military facilities underground, limiting the effectiveness of airstrikes. If the United States decides to attack North Korea without attempting to eliminate its ballistic missile and WMD capabilities, it would leave itself and its allies at Kim’s mercy. If, on the other hand, the United States is determined to keep going until North Korea has been completely denuclearized, it must consider the potential consequences of a full-scale invasion.

A general war with North Korea would be devastating. A recent report by the Congressional Research Service estimated that between 30,000 and 300,000 people could die in the first days of fighting, even if Pyongyang refrained from using any weapons of mass destruction—an unlikely scenario. According to recently declassified U.S. government documents, moreover, in 1994 the Pentagon estimated that a war on the Korean Peninsula would kill or injure 52,000 American servicepeople and over 490,000 South Korean troops in just three months of fighting. Those numbers have almost certainly gotten far worse in the intervening 24 years, given North Korea’s tremendous progress in developing weapons of mass destruction. Today, millions of lives could be threatened.

To provide some perspective, over 6,900 U.S. military personnel have been killed and over 52,000 have been injured in Iraq and the surrounding area since 2003. Although no one knows how many civilians have been killed in that war, academics estimated that 461,000 people died in Iraq as a result of war-related causes between 2003 and 2011, and thousands more have died in the years since. And according to research conducted at Brown University, as of 2015, at least 970,000 veterans from Iraq and Afghanistan have some degree of officially recognized disability as a result of the wars; when considering the costs of war, these count as well. A war with North Korea would likely be more devastating than any conflict the United States has experienced since World War II, if ever.

Beyond the human cost, a war on the Korean Peninsula would be catastrophic for the global economy. China, Japan, and South Korea are some of the largest economies of the world, representing 20 percent of global GDP. They are the first-, fourth-, and sixth- largest trade partners of the United States, representing over $880 billion in trade in 2016 alone. A war would decimate trade and investment in the region and would be an economic disaster for the United States.

DIMINISHED AMERICAN POWER

A war would not only risk lives and treasure—it would risk U.S. power, too. If the United States starts a conflict with North Korea or fails to achieve its objectives in a limited strike, it is likely to witness a significant diminution of its geopolitical power across the Asia-Pacific.

The United States’ key allies in the region, South Korea and Japan, are unlikely to support a preventive U.S. strike on North Korea. In fact, South Korean President Moon Jae-in has already claimed the right to veto any U.S. military action on the peninsula. This is unsurprising, as a conflict would put the lives of millions of Japanese and South Korean civilians at risk. Although both countries support pressuring North Korea and fully expect the Washington to come to their defense if attacked, neither has voiced any support for the United States precipitating a conflict. In fact, scholars and officials privately express the opposite: fear that the United States will start a war and they will pay the price.

If Washington initiates a conflict and Pyongyang escalates, Seoul and Tokyo may consider significantly curtailing (or even ending) their alliances with the United States, ejecting U.S. armed forces from their territory, and developing their own nuclear weapons. This would effectively end U.S. geopolitical dominance in the Asia-Pacific, creating a region riven with division and instability, with diminished U.S. power and influence and China poised to fill the void.