What a U.S. missile defence system and a new president mean for South Korea

U.S. installed an anti-ballistic missile system in South Korea late last month.
Ernie Regehr looks at why it has caused debate and the strategy new president
Moon Jae-in would rather promote.

By: /
11 May, 2017
Seoungju residents take part in a protest against the government's decision on deploying a U.S. THAAD anti-missile defence unit in Seongju, in Seoul, South Korea, July 21, 2016. REUTERS/Kim Hong-Ji
By: Ernie Regehr

Senior Fellow, The Simons Foundation

South Koreans within the firing range of Kim Jong-un’s brandished missiles and nuclear warheads might be expected to welcome protection wherever it can be found, but they remain far from united on the question of hosting American missile defence batteries on their soil.

Indeed, in Moon Jae-in, they’ve elected this week the presidential candidate most critical of the rushed deployment of the United States’ anti-ballistic missile system known as the Terminal High Altitude Area Defense (THAAD).

In Seonjgu, where a local golf course became THAAD’s home base in late April, protesters have focused largely on local implications of deployment — safety concerns and worries that they will or could now be targeted. Other THAAD opponents focus more on the strategic implications — increased dependence on the U.S., South Korea’s primary security partner, and worsening relations with China, its primary economic partner.

South Korean doubts are also fanned by questions about the system’s performance. The Pentagon points to 42 tests yielding 35 successful intercepts, but others, notably George Lewis and Ted Postol, two noted Ballistic Missile Defence (BMD) experts and critics based at the Massachusetts Institute of Technology, say the tests were not conducted under real-word conditions and, had they been, most of the “successful” interceptions would in fact have failed to destroy attacking warheads.

There is another problem. While THAAD might be effective against isolated attacks, North Korea is already practicing barrage attack techniques with its older, tried and proven extended range Scud missiles. As the experts explain, swarm-like attacks could overwhelm the system’s radars and in turn render the interceptors unreliable. The obvious North Korean response will be the even more determined build up of its inventory of attack missiles to ensure it can overwhelm any regional defence capacity. Adding attack missiles will always be a lot cheaper than building credible nation-wide defences in South Korea.

Still another source of doubt is the range of the THAAD interceptors. Their operations are confined to a radius of about 150 kilometres around each of the system’s two launch units, leaving rather large parts of the population, including the 25-plus million people living in and around Seoul, not even theoretically covered. Furthermore, THAAD has no capacity against North Korea’s massive concentration of artillery within range of Seoul. 

A threat to China

On balance, THAAD promises to deliver minimal protection while seriously complicating South Korea’s strategic posture.

Part of that complication owes to China’s concern about the THAAD system’s radar reach into its own air space. The U.S. has assured Beijing that, even though those radars have the potential to monitor airspace over Chinese territory, the U.S. configures them in a short-range mode and focuses them on North Korea. But that would not prevent the U.S. from reorienting its missile detection and tracking radars, even for short periods, to substantially increase their reach into Chinese territory. These regional radars have the capacity to feed data to the strategic ground-based BMD system, with its Alaskan and California interceptors, thus giving that system an enhanced capability for tracking and ultimately intercepting Chinese intercontinental missiles.

And that’s not only a problem for China. If China concludes that its second-strike deterrent is under threat, or could be in the future, it might abandon its policy of keeping its intercontinental missiles thoroughly de-alerted, with warheads maintained separately from missiles under normal conditions. Indeed, that policy is a model that the U.S. and Russia should adopt to reduce the risk of accidental or false alarm launches of their strategic nuclear missiles. But if American BMD intensification leads China to switch to launch-ready deployments, the world will have become more dangerous for all of us.

Diplomacy remains restrained to the point of paralysis.

While inflammatory rhetoric and military action meant to intimidate have escalated, diplomacy remains restrained to the point of paralysis — despite some evidence of Kim Jung-un’s openness. A July 2016 North Korean declaration, ignored by the U.S. but worthy of more attention than it got, linked resumed denuclearization talks to some familiar demands: disclosure of all U.S. nuclear weapons in and around South Korea, a commitment never to reintroduce nuclear weapons into the region, and an end to all nuclear-use threats against the North (that being the same kind of negative security assurance that, by Security Council resolution, is owed to all states that fully disavow nuclear weapons).

Those demands recall the 2005 joint statement that came out of the six-party talks involving China, the U.S., North and South Korea, Japan and Russia. The key elements then were: agreement on the objective of a verifiably denuclearized Korean Peninsula; elevating the 1953 armistice into a permanent peace agreement (the implications of which are acceptance of the North Korean state and the disavowal of regime change ambitions by the U.S.); economic cooperation with North Korea in energy development, trade and investment (and initially, at least, a major expansion of humanitarian assistance).

Diplomacy going forward

You won’t find a lot of experts who think such a grand bargain is within early reach. Kim Jong-un remains too much of an enigma to South Korean and Western interlocutors for them to presume they truly understand the regime’s expectations and interests, but there really is only one antidote to the “mystery” of North Korea, and that is engagement. Engagement doesn’t begin with either agreement or preconditions, nor does it normally begin with formal talks, but multi-level and multi-forum explorations need to become the norm. Informal but sustained contacts among officials and experts, academic-level discussions and conferences, citizen-to-citizen engagement — all are means of breaking through barriers of incomprehension.

Targeted sanctions, reversible in response to North Korean cooperation, along with diplomatic engagement, are more likely to yield progress, it goes without saying, than are the quixotic lurches of the Trump administration.

While the current stalemate unfortunately affords the North time and opportunity to further develop its nuclear capabilities, it could also yield a new round of diplomacy aimed at identifying interim steps toward the ultimate deal — an effort South Korea’s new president, Moon Jae-in, has promised, and that Canada and other like-minded states should be promoting.

Denuclearization of the Korean Peninsula is essential for stability and safety in the region, but it is also essential for nuclear disarmament writ large. To leave North Korea indefinitely in possession of a nuclear arsenal, even a modest one by global standards, is not acceptable. Accepting North Korea with a permanent nuclear arsenal would in effect be tolerating an international non-proliferation regime incapable of preventing a formerly non-nuclear-weapon state party to the Nuclear Non-Proliferation Treaty, a state thus legally bound to eschew such weapons, from acquiring nuclear weapons. And one certain consequence of accepting such a major non-proliferation failure would be to also render progress in nuclear disarmament an ongoing failure.

As for THAAD in South Korea, its deployment does little for safety, stability or disarmament in the region. The system’s limited capabilities and inability to offer protection for the densely populated Seoul region belie its safety claims; its impact on China undermines strategic stability; and inasmuch as it creates incentives for North Korea to expand its inventory of missiles and warheads, it undermines disarmament.

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