On July 7, 2016, the U.S. and South Korean governments announced a joint decision to deploy the U.S. Terminal High Altitude Area Defense (THAAD) missile system in South Korea.

The two governments assert, without serious evidence and contrary to expert opinion, that the THAAD system will protect South Korea from the threat of North Korean missiles. For example, the U.S. Congressional Research Service finds that THAAD is unlikely to shield South Korea since it is designed to counter high altitude missiles, not those that North Korea would likely use against South Korean targets.

Moreover, the decision to deploy THAAD in South Korea, and to continue with last summer’s U.S.-South Korea war games, occurred in spite of offers by North Korea to freeze its nuclear weapons programs if Washington and Seoul would stop the war games. North Korea has since continued testing its ballistic missiles; it conducted its fifth nuclear explosion, September 9, 2016, and continues to pursue its goal of fitting a nuclear warhead on top of an ICBM missile.

The U.S. THAAD deployment in South Korea is part of the U.S. “pivot” to the Asia Pacific. It expands the already significant network of U.S. “missile defense” systems encircling China and Russia. These systems give the United States a significant, although fleeting, military advantage in any future confrontation since they give the United States military the potential to neutralize an opponent’s ability to retaliate. The expansion of this network appears to reflect a broader U.S. decision to change its military posture from one of deterrence to that of first strike.

The determination of the US government to use an expanding regional military presence to boost its regional political influence comes at high cost. For example, this strategy intensifies regional military tensions, fuels a new arms race, and increases the possibility of a new war on the Korean peninsula. In doing so, it also undermines the national sovereignty and democratic aspirations of people in other countries, in this instance those in South Korea.

A growing number of South Koreans are fighting to block deployment of the THAAD system in their country. They correctly fear that its deployment will draw their country into an anti-Chinese alliance with the United States and Japan, embolden militaristic and anti-democratic political forces in their own country, and exacerbate tensions between North and South Korea. They also worry about the negative health effects that appear associated with the operation of the THAAD radar system. Also of concern is the cost of the THAAD system–estimated at $1.3 billion, plus an additional $22 million each year for operating and sustainment–will be borne by South Korean and U.S. taxpayers.

Very little is known in the United States about THAAD and the opposition of South Koreans to its deployment in their country, and of recent diplomatic overtures by North Korea to reduce tensions on the peninsula. Yet, its deployment should also be of concern to people in the United States.  We also will suffer if our country again goes to war. And even if the worst is avoided, the continuing development of new and more destructive weapons systems draws precious resources away from needed domestic social programs.

After decades of disastrous military engagements abroad, we need a new approach. We urge the U.S. government to move away from policies that escalate military tension and redraw Cold War-era lines in favor of policies that seek to resolve conflicts, peacefully, through diplomacy and dialogue. Toward that end, we urge the U.S. government to rescind its decision on THAAD deployment in South Korea, and to pursue all possible avenues for reducing tensions on the Korean peninsula by re-engaging in diplomacy with North Korea.