We shouldn’t have to say this, but starting a war on the Korean Peninsula is a bad idea. I am not the first person to make the case that a war on the Korean peninsula would be bad for America —and for South Korea and probably for Japan. Recently, professor Barry Posen laid out just how difficult it would be to conduct a successful pre-emptive attack against North Korea. He further presented how terrible a conflict on the peninsula would be in terms of lives lost — North Korean, South Korean and American. Professor Posen’s piece, however did not go far enough in explaining how a pre-emptive attack — and then war — on the Korean peninsula would damage U.S. interests.
With the administration’s statements leaving the door open to a pre-emptive strike against North Korea, it is a good time to catalogue why such a concept is a bad idea—regardless of one’s view of the threats posed by the North Korean regime and its nuclear and missile programs. Professor Posen captures the likely human toll of a second Korean war well. The costs of the conflict and its aftermath would leave the United States and its allies poorer. And ultimately, the United States would likely be less secure than it is today.
Difficulty of Escalation Control
North Korea has signaled, for decades, that any attack against it would be met with swift retribution. For much of the post-Korean War era, this meant massive artillery bombardment of Seoul. Now that North Korea possesses missiles with intercontinental range, that retribution could be against targets as far away as New York or Washington. The idea that the United States could conduct strikes against limited targets—such as North Korea’s missile facilities or nuclear weapons complexes—with little to no North Korean response is gambling with millions of lives at stake. Were North Korea to follow through on its repeated statements of retaliation, and a U.S. or allied territory to be struck, it would likely result in activation of one or more of the U.S. mutual defense treaties, and the commitment of significant U.S. forces to a conflict on the Korean peninsula. At that point, what was presented as a limited strike will have become a full-blown war.
It is therefore critical to recognize the limits of escalation control when dealing with military options against North Korea. And Professor Posen makes a clear and compelling argument about the likely catastrophic human consequences of such a conflict. One must also consider additional strategic consequences for the United States, specifically the financial toll and effect on regional alliances.
The Financial Toll
North Korea’s active-duty military is estimated to number over 1 million personnel. South Korea maintains a 650,000-person army. Even if the combined U.S.-South Korean force is better trained and equipped than its North Korean adversary, North Korea has spent nearly 70 years developing hardened shelters and stowage points for its personnel and artillery pieces. The four kilometer-wide De-Militarized Zone (DMZ) is also the most heavily mined area on the planet, limiting the ability of ground forces to move through it easily.
North Korea is believed to have developed tunnels across the DMZ to move its army or special forces rapidly into South Korean territory — and to bypass the mines laid along the DMZ. Even assuming U.S. and South Korean ground forces can quickly move through the DMZ to the North, the mountainous terrain would make rapid ground movement difficult—especially with heavy tanks or artillery. All of this is before considering the impact of North Korea’s nuclear weapons or its stockpiles of chemical weapons and biological weaponswould have on the conflict.
The sum of these factors suggest that prosecuting a war in North Korea has the potential to be more expensive than the $1.5 trillion spent so far on the conflicts in Iraq and Afghanistan. Winning the war would be only a small portion of the total costs, however. The real costs to the United States—and South Korea—would come from the needed investments to develop North Korea’s economy and rebuild its society after a successful military campaign, and to rebuild the portions of South Korea destroyed in a war.
By way of comparison, 20 years after the reunification of Germany, Germany’s Finance Minister stated that the annual cost of reunification was approximately 100 billion euros per year—or nearly 2 trillion euros. East Germany’s per capita GDP was, at the time of reunification, approximately one half of West Germany’s. North Korea’s GDP today is only 3 percent of South Korea’s.
The Regional Security Consequences
Even if it wins, the United States could find itself less secure in Northeast Asia after a war with North Korea.
China has long been concerned about U.S. military presence in Korea, believing U.S. forces there could pose a threat to China’s sovereignty and security. Should the U.S.-ROK force prevail against North Korea in a war, the long-standing basis for keeping U.S. troops on the Korean peninsula — to defend South Korea from North Korean invasion — would be moot. China would likely push the South Korean government (especially if it were the de facto government of the entire Korean peninsula) to change its relationship with the United States and reduce or eliminate U.S. forces from the peninsula.
Should U.S. forces leave the Korean peninsula, China would likely use the withdrawal to build a narrative that the United States is retreating from Asia, that it is not a reliable security partner, or both. Consequently, the United States would have less diplomatic credibility, less military capability, and less influence with allies in the region.
A potentially more dangerous — and more likely — scenario is that the United States could find itself with troops dangerously-close to China’s border. It was Chinese fear of U.S. encroachment on its border that led Mao Zedong to intervene in the Korean War on North Korea’s behalf in 1950. With U.S. and Chinese troops mere miles apart, the risk of a U.S.-China stand-off escalating quickly from a skirmish to a major exchange would increase.
From China’s perspective, the continued existence of North Korea as a separate country provides a buffer between its own borders and U.S. forces. A unified Korean peninsula, with U.S. troops still present, would be perceived as negatively impacting China’s security.
The likely result of fighting a war against North Korea to eliminate the threat that it would use its nuclear weapons against the United States or its allies is that the United States would instead increase the likelihood of conflict with far more potent nuclear-armed adversaries in China.
Deterrence: A Better Deal
With war on the Korean peninsula too costly, from human, economic, and security perspectives, what options remain? Fortunately for the United States and our allies in Asia, managing new nuclear powers is something the United States has experience with, and it is called deterrence.
The window to remove North Korea’s nuclear weapons by force has passed. Instead, the United States will need to work with allies and partners to ensure North Korea understands the consequences of its continued reliance on those weapons, and the implications for North Korea’s future if those weapons are used. Additionally, the United States will need to continue working with South Korea and Japan to maintain a unified approach toward North Korea.
All three allies will also have to work closely to pressure China and Russia to deter North Korea’s continued pursuit of a nuclear weapons program, and especially toward using those weapons in the future.
The number of countries that have closed their embassies in North Korea and who have shown a willingness to work with the United States to limit North Korea’s access to financing and materiel speaks highly of the potential for focused and patient diplomacy. Ensuring the United States and South Korea remain positioned to respond to North Korean aggression, should it happen, is essential. Maintaining the diplomatic pressure that has begun to bear fruit will also be essential if the United States is to avoid a situation where through impatience it turns a strategically difficult situation into a strategic setback.