Editor’s note: Professor Zhou Yongsheng is the director of the Institute of International Relations and the deputy director of the Center for Japan Studies, China Foreign Affairs University. The article reflects the author's opinions, and not necessarily the views of CGTN.

Just a few days after the G20 summit in Osaka, Japan announced to tighten controls on exports of hi-tech materials to the Republic of Korea (ROK) on July 1, which took effect on July 4. In response, the ROK not only asked for negotiations with Japan, but also urged the United States to intervene. ROK's Foreign Minister Kang Kyung-wha, made a telephone conversation with U.S. Secretary of State Mike Pompeo and explained ROK's stance over the issue and asked for U.S. intervention. Pompeo, however, indicated that he would strengthen communications between the U.S., Japan and the ROK.

Apparently, the U.S. does not plan to figure it out. David Stilwell, U.S. Assistant Secretary of State for East Asian and Pacific affairs, visited Japan from July 11 to 14, before heading west to the ROK on July 17. In an interview, he said that the U.S. would not intervene in the current conflicts between Japan and the ROK over trade and history.

There are several reasons behind it.

First, in recent years, under the current ROK administration led by Moon Jae-in, positive changes have taken place in north-south relations, moving from hostility to mitigation of tensions, and progress has been made toward the establishment of a peace mechanism on the Korean Peninsula.

However, ROK's stance on DPRK has arguably irritated the U.S. that will lessen U.S. influence in the region. What's more, Washington doesn't want to show their true color, because the U.S. still hopes the ROK to play an important role in the process of denuclearization.

Furthermore, as an ally of the U.S., despite its different policy toward the DPRK, the Moon Jae-in administration maintains frequent contact and timely communication with the U.S. over the DPRK issue. It makes the U.S. hard to find an excuse to criticize the ROK. To some extent, Japan's export controls represent Washington is willing to warn Seoul keeping on its side over the DPRK issue.

Second, Trump's trade bullying enables China, Japan and the ROK to form closer trade ties based upon their shared interests. With the escalating trade disputes with China and sanctions on Japanese and Korean steel products, there has been a growing wave of public discontent to "America first" and its unilateralism among the three countries.

Voices from the business, academic and political communities across China, Japan and the ROK have repeatedly called for safeguarding the world's free trade system. Rattled by such rising solidarity, the U.S. administration seeks to take advantage of the Japan-ROK trade disputes to sow discord among the three countries for the purpose of preventing them from forming a joint force to safeguard the existing system of the World Trade Organization.

Third, officials from China, Japan and the ROK have expressed their willingness to speed up the process of signing the China-Japan-ROK free trade agreement and strive to reach a trilateral free trade agreement at an early date. On May 10, 2019, Chinese State Councilor and Foreign Minister Wang Yi expressed China's wish to accelerate the negotiation process of the free trade zone agreement between China, Japan and the ROK during the International Forum on Cooperation among the three countries.

At the same time, Yutaka Yokoi, Japanese ambassador to China, said that in an international community with rising protectionism, Japan, China and the ROK must enhance their mutual cooperation. For Washington, Beijing, Seoul and Tokyo's improved ties create fears of being marginalized in East Asia. Therefore, the trade disputes between Japan and the ROK could be used by the "Uncle Sam" as a way to shatter trade ties among China, Japan and the ROK.

Fourth, it's no coincidence that conflicts arose between the three countries when their relationships were improving, and they were inching closer to signing trade trades. The collision between a Chinese fishing boat and Japanese patrol boat in 2010, and Japan's purchase of three disputed islands in 2012 are cases in point. The U.S. was believed to be instrumental in both of these conflicts.

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