Following frightening improvements in North Korea’s nuclear and missile technologies, South Korea earlier this year deployed THAAD, an American-made missile defense system. China responded by retaliating against South Korea. Lacking support from the United States and Japan—both of whom benefit from the THAAD deployment—Seoul recently caved to Beijing’s pressure to halt further missile defense and other military cooperation with Washington and Tokyo. The failure by the United States and Japan to back South Korea is a troubling sign to other Asian countries. Regional capitals now understand that they should not put too much faith in Washington or Tokyo because if they do, they may be disappointed and could face Beijing’s ire alone. If the United States and Japan continue to project this sense of detachment, Asian countries may gravitate towards China as it vies to supplant the American-led regional order.

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THAAD is an advanced missile defense system with a powerful radar. The United States deploys it in Guam to counter North Korean attacks because the system functions best against the types of missiles Pyongyang would use if it targeted that island, South Korea or Japan. THAAD can also integrate with other missile defense systems, including the Aegis and Patriot varieties used by Washington, Seoul and Tokyo. Such integration would provide greater protection for all three countries by identifying missile launches earlier and intercepting missiles at different trajectory points.

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Since 2014, Washington has urged Seoul to acquire THAAD and to join a U.S.-led integrated missile defense network to better restrain Pyongyang. South Korea resisted, buckling in large part to previous pressure from its largest trade partner and more powerful neighbor, China. Beijing fears THAAD impairing its nuclear deterrent and being used for espionage. More broadly, China opposes any deeper military cooperation among the United States and its Asian allies.

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But since 2016, the North Korean threat has grown at an unprecedented rate. Pyongyang has successfully tested increasingly powerful nuclear weapons and missiles, expanded its arsenal, and improved its ability to elude missile launch detection. Experts believe North Korea could soon strike the continental United States with a nuclear-tipped missile. America and Japan thus benefit from a stronger missile defense system in South Korea.

In response, South Korea announced plans in July 2016 to deploy a THAAD battery in its territory. Installation concluded in September 2017.

To force Seoul to abandon THAAD, China began punishing South Korea as soon as it announced the deployment. Chinese retaliation included suspending military contacts, denying visas, cyberattacks, a government-encouraged boycott of South Korean products and services, and the closure of South Korean businesses in China—including the company that provided land for Seoul’s THAAD battery. In May 2017, a research group estimated that China’s economic coercion would cost South Korea about $7.5 billion in 2017, resulting in a 0.5 percent GDP drop.

This retaliation is the most aggressive example of China’s recent economic punishment on countries that it believes are threatening its security interests. In 2010, China temporarily ceased exporting rare earth minerals to Japan following an altercation in contested waters, and it boycotted Norwegian salmon for six years because a Chinese dissident received the Nobel Peace Prize. In 2012, after a row over disputed territory, China blocked Filipino fruit from passing its ports. Last year, China reduced the number of its tourists visiting Taiwan because that country elected a pro-independence president.

China agreed last month to cease targeting South Korea. But the fallout continues, as Washington’s and Tokyo’s failure to fully back Seoul in the face of Chinese bullying may have larger consequences throughout the region.

When it became clear that Beijing was seriously sanctioning Seoul, Washington and Tokyo should have forcefully denounced the move, imposed joint economic countermeasures against China and offered favorable trade terms to South Korea. This collective response would have demonstrated that a powerful network will oppose Chinese overreach and support countries that favor the United States and its partners. Moreover, it could have improved the rocky Japanese–South Korean relationship that is vital to deterring Chinese aggression.

Unfortunately, the United States and Japan watched China’s bullying from the sidelines. Compounding that fecklessness, Washington abandoned the Trans-Pacific Partnership—a free trade agreement large enough to offset creeping Chinese influence—and threatened to end its free trade agreement with Seoul. Meanwhile, China continues to forge its own regional trade group and to secure significant infrastructure investment deals to help project its military power far beyond its borders. The message is clear: China is vying to fill a growing leadership vacuum in Asia, its power grabs may go unchecked, and China’s weaker neighbors should not adopt policies that risk angering it.

Countries in Beijing’s shadow are already hedging. After the Chinese–South Korean rapprochement, Seoul announced that it will acquire no additional THAAD batteries, although its current installation does not cover the entire country. Seoul also pledged to forego integrating with Washington’s and Tokyo’s missile defense systems, and to eschew a trilateral military alliance with them. And just days ago, Manila followed Beijing’s command to halt construction in waters claimed by both countries. This appeasement trails the Philippines recently declaring its “separation” from its long-time treaty partner, the United States, and downplaying its territorial conflict with China.

America should not intervene every time China pressures its Asian friends. Doing so would invite those countries to act too aggressively with China and discourage their development of self-defense capabilities, as well as frequently risk serious confrontations between Washington and Beijing. But when U.S. leadership is doubted and Chinese actions threaten America’s vital security interests, Washington must respond appropriately, and preferably alongside its Asian partners. Collective countermeasures are less likely to arouse major Chinese retribution, and they will deepen integration among the United States and its friends in Asia.

President Trump must repair the damage caused by the America and Japan watching South Korea bow to China on missile defense. Asian “swing states”—countries deciding whether to follow the United States or China as they compete for regional leadership—are anxiously watching.

Paul J. Leaf is a regular commentator on U.S. foreign policy. He worked on defense issues for a think tank and is now an attorney at an international law firm.

Image: Reuters

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