With North Korea preparing to strike southward, and the United States deeply ambivalent about its defense, Seoul needs nuclear weapons now more than ever.
North Korea’s nuclear weapons development is proceeding faster than expected, with monumental recent advances. Notably, Pyongyang has announced that it has built a nuclear-powered submarine for itself—likely with Russian assistance. This would, if true, make North Korea’s growing nuclear weapons arsenal truly robust, and give Pyongyang the ability to annihilate their U.S.-supported South Korean neighbors.
Although South Korea possesses the technological sophistication to build their own nuclear weapons, Seoul has for years refused to develop its own nuclear arsenal, choosing instead to rely upon American security guarantees. But between the rapid development of North Korea’s nuclear weapons program and the increasingly unpredictable level of U.S. support for South Korea’s defense, it is past time for the South Korean leadership to reassess its refusal to develop its own nuclear weapons deterrent.
Put simply, South Korea’s nuclear missile defenses are totally insufficient to the kind of devastation that the combined capabilities—both nuclear and non-nuclear—that North Korea could deploy against its southern neighbor, if Pyongyang chose to initiate a conflict. The best defense against such a threat is a good offense. The Kim regime must be afraid that if it launched such an attack against Seoul, Seoul would annihilate it in turn.
South Korea’s THAAD System Cannot Stop the North
To counter North Korean missiles, Seoul has developed a multi-layered missile defense system that is designed to intercept threats at various altitudes and ranges. One key asset in this layered defense system is the Terminal High Altitude Area Defense (THAAD) system, which has been deployed in South Korea since 2017.
THAAD is an American-built system that is designed to intercept short, medium, and intermediate-range ballistic missiles during their terminal phase. It employs a hit-to-kill approach and has a range of 200 miles and can hit incoming missiles as high as 93 miles in the atmosphere.
THAAD comes equipped with an AN/TPY-2 radar that provides advanced tracking, crucial for detecting and intercepting North Korean launches from just across the De-Militarized Zone (DMZ). Interestingly, the THAAD was a major point of contention during the first year of President Donald Trump’s uneven first term. Back then, the president opposed the deployment of this system, on the grounds that Seoul was not paying enough to the Americans for their defense and was effectively harming the U.S. economy by negotiating one-sided trade deals over the course of decades.
Although he conceded the economic issue, Trump’s first secretary of defense, retired Marine Corps General James Mattis, urged the president to support the deployment of THAAD, as it enhanced South Korean security, but it also expanded America’s ability to detect—and possibly shoot down—North Korean nukes.
Yet, as the Ukraine War has shown, the American THAAD system is inherently limited due to the poor state of America’s defense industrial base. Although the system performs well, there are insufficient levels of ammunition available—as well as an overall shortage of THAAD systems available, meaning that the system would not be truly effective against swarms of nuclear missiles.
South Korea Is Making Domestic Missile Defenses—But Not Fast Enough
Another critical system that South Korea has is its indigenously built KM-SAM (Cheongung). A medium-range surface-to-air missile system that has been operational since 2016, this system can intercept missiles at altitudes of up to 24 miles away and 24 miles in the air. KM-SAMs have anti-jamming capabilities to ensure reliability against North Korean electronic countermeasures.
While primarily aimed at lower-altitude threats, the KM-SAM complements the THAAD by covering shorter-range missiles that might carry nuclear warheads.
For a broader range, South Korea has integrated the American-made Patriot PAC-3 system. These excel at point defense against short-range ballistic missiles and aircraft, intercepting targets at altitudes of up to 12-18 miles away.
Therefore, the Patriot PAC-3 fills the gap between the THAAD and KM-SAM. Unfortunately, this system is not fully deployed, although tests in recent years suggest it could soon bolster defenses against North Korea’s more advanced ballistic missiles.
A key reason for the Patriot PAC-3 not being fully deployed is because of the aforementioned defense industrial base woes of the United States. America cannot keep up with the growing panoply of global threats arrayed against itself and its allies.
Similarly, the South Koreans are feverishly developing the Long-Range Surface-to-Air Missile (L-SAM). That is an advanced missile defense system that is meant to counter the Hwasong-series of advanced North Korean ballistic missiles. L-SAM is intended to engage targets at lower altitudes, between 24-62 miles away.
This system is meant to fill the gap with the KM-SAM. It is a critical mid-tier layer in South Korea’s missile defense architecture. Sadly, though, the L-SAM probably will not be available until the end of the decade, leaving a critical gap in South Korea’s missile defense.
South Korean anti-missile defense systems work best in conjunction with other American (and Japanese) assets, such as the Aegis-equipped naval destroyers, under a joint missile defense framework.
North Korea’s nuclear missiles, such as the Hwasong-17 intercontinental ballistic missile (ICBM), pose real challenges to South Korea’s defense system because of the Hwasong-17’s high speed and potential for decoys.
Even then, the reliability of these defenses, when taking into account the incredible dynamism of North Korea’s nuclear weapons threat, is suspect.
A Simple Solution: South Korean Nukes
For too long, the American bipartisan foreign establishment has zealously pursued nuclear non-proliferation, even as it led to growing foreign security guarantees and mounting U.S. obligations abroad. Washington has acted decisively to prevent Seoul from developing a robust national defense capability, notably in the form of nuclear weapons. In so doing, it has infantilized it, leaving it severely underequipped to handle the threat to the north. Today, as a result, there is a severe imbalance in security on the Korean Peninsula that now favors Pyongyang.
It is beyond time for Washington to change its approach. The Trump administration should tell its South Korean allies that, because of the severe strain on the U.S. defense industrial base—as well as its real umbrage with South Korea for having gotten the better end of a succession of trade deals—Seoul must stand on its own.
And the only reliable way for South Korea to stand on its own is for it to rapidly develop an arsenal of advanced nuclear weapons that will serve as a deterrent against the hostile North Koreans. Fortunately, South Korea is fully capable of this: it has a number of nuclear reactors and full mastery over its nuclear fuel cycle, and could put together a handful of plutonium bombs within the year. A more sophisticated program—and perhaps eventually a full nuclear triad—will soon follow.
But no amount of ground-based, hit-to-kill missile defense systems will provide the kind of comprehensive deterrence against the North’s nuclear weapons arsenal that a rival nuclear weapons arsenal in the South can provide.
This is the essence of deterrence—and that basic fact has been forgotten in the hurly-burly of America’s post-Cold War “unipolar moment.” With that moment long over, it’s time for South Korea to grow up fast, lest it be overrun by stronger rivals.
About the Author: Brandon J. Weichert
Brandon J. Weichert, a Senior National Security Editor at The National Interest as well as a contributor at Popular Mechanics, who consults regularly with various government institutions and private organizations on geopolitical issues. Weichert’s writings have appeared in multiple publications, including the Washington Times, National Review, The American Spectator, MSN, the Asia Times, and countless others. His books include Winning Space: How America Remains a Superpower, Biohacked: China’s Race to Control Life, and The Shadow War: Iran’s Quest for Supremacy. His newest book, A Disaster of Our Own Making: How the West Lost Ukraine is available for purchase wherever books are sold. He can be followed via Twitter @WeTheBrandon.
Image: Anton Watman.
