Last week, South Korean President Park Geun-hye, despite the opposition of her country’s closest ally, the United States, stood together with Chinese President Xi Jinping in Tiananmen Square to watch the military parade commemorating the 70th anniversary of World War II’s end in Asia.

The decision provided the most visible image yet of an emerging China-South Korea alliance, one that China believes may prevent the region from sliding into cold war.

The region’s other major actors — the U.S., Japan, and even North Korea — look upon this blossoming friendship with considerable dread. The U.S. worries that China is driving a wedge between its strongest Asian allies, South Korea and Japan, undermining America’s capacity to offset China’s rising military power.

Likewise, Japanese Prime Minister Shinzo Abe is concerned that his country’s closest neighbor is drifting into China’s orbit. And, indeed, Park has consistently spurned Abe by refusing to hold a bilateral summit with him, in protest over Japan’s alleged historical revisionism, particularly with regard to the Korean “comfort women,” who served as sex slaves for the Imperial Japanese Army during WWII.

For North Korea — which already has to contend with South Korea’s alliance with the U.S., including seemingly endless joint military exercises — the South’s budding friendship with China, the North’s longtime ally, probably seems even more threatening. That may explain why just a few hours after Park’s trip to China was announced, the Koreas traded artillery fire. Fortunately, the two sides quickly reached a deal — probably brokered by China — to end the military standoff.

But the Korean Peninsula is likely to experience a new round of turbulence soon. The upcoming 70th anniversary celebration of the founding of the ruling Workers’ Party of Korea will reportedly entail a large-scale military parade and a ballistic missile test. And, according to Siegfried Hecker, the former director of the Los Alamos National Laboratory in the U.S., North Korea will have 20 warheads in its nuclear arsenal by 2016; it also plans to move rapidly to develop its capacity to miniaturize nuclear weapons.

In this context, it seems likely that historical grievances with Japan are far from the only issue driving South Korea toward China. America’s failure to push urgently for the denuclearization of the Korean Peninsula — a position that stands in stark contrast to the concerted effort made to reach a nuclear deal with Iran — is a serious problem for the South. China seems more important than ever to achieving South Korea’s goal of restarting the long-stalled six-party talks to address the North Korean nuclear threat.

To be sure, South Korea and China remain deeply divided over their policies toward North Korea. Nonetheless, the denuclearization of the Korean peninsula, key to ensuring long-term regional stability, is in the interest of both countries — as well as Japan.

None of this means that South Korea is abandoning the U.S. in favor of China. Rather, Park wants South Korea to serve as a bridge between the two powers. China seems to appreciate Park’s middle-power diplomacy, owing to its economic interest in avoiding the emergence of two rival blocs in Asia — an interest that is reflected in Xi’s upcoming state visit to the U.S.

In the past, Xi’s state visits have often coincided with significant strides in bilateral cooperation. His visit to Seoul last year yielded South Korea’s pledge of support for the China-led Asian Infrastructure Investment Bank — again, over U.S. objections. And this past June, the two countries signed a free-trade agreement.

China viewed America’s strong resistance to the AIIB — which it considered a clear challenge to the U.S,- and Japan-led international financial institutions — as an overreaction, reflecting America’s tendency to view nearly all China-related policies through the lens of strategic competition. And, indeed, it seems that an “anything-but-China” mentality prevails among many U.S. decision-makers, whether in economic or security affairs.

Even as China’s leaders seek to deepen ties with a variety of countries, including the U.S., American policymakers view South Korea’s pursuit of closer ties with China as a direct threat to their country’s regional primacy. That is why the U.S. has been pressing South Korea to express more explicitly its opposition to China’s behavior regarding its territorial claims in the South China Sea.

The U.S. approach is gravely misguided. As the former diplomat Thomas Christensen points out in his recent book “The China Challenge,” China “has major incentives to avoid unnecessary conflict.” The problem is that the U.S. lacks experience in “persuading a uniquely large developing country with enormous domestic challenges and a historical chip on its national shoulder to cooperate actively with the international community.” In other words, U.S. policymakers’ “zero-sum” mentality is not only wrong; it is impeding America’s ability to harness China’s influence to enhance, rather than undermine, regional stability.

In late May, at the 14th Asian Security Summit, U.S. Secretary of Defense Ashton Carter called for a “shared regional architecture” that will enable all Asia-Pacific countries to rise peacefully. That is the right approach.

But such an architecture will be impossible to achieve as long as the U.S. is pressuring its allies to alienate, if not antagonize, China. The U.S. should be encouraging allies like South Korea, Australia, and Thailand (but not Japan and the Philippines, given their involvement in territorial conflicts with China) to engage further with China. Only then can the U.S. secure China’s cooperation in confronting urgent regional challenges and win its commitment to a rules-based and inclusive regional order.

By Minghao Zhao

Minghao Zhao is a research fellow at the Charhar Institute in Beijing, an adjunct fellow at the Chongyang Institute for Financial Studies at Renmin University of China. — Ed.