The February meeting between Prime Minister Shinzo Abe and U.S. President Donald Trump will likely be remembered in the long history of summits between top leaders of Japan and the United States in the postwar years — beginning with the 1951 talks between Shigeru Yoshida and Harry Truman — for the extraordinary welcome with which the host U.S. president received the visiting Japanese prime minister. The Abe-Trump summit was also unprecedented in terms of the difficulty of reconciling its agenda, priorities and negotiation processes between the two sides.

Ahead of the summit, Tokyo’s greatest fear was that the new Trump administration would demonstrate little interest in the shared values of the U.S. and its allies, and would instead seek to link different areas to its advantage when negotiating with Japan. As it prepared for the talks, the Japanese side took pains to ward off any attempt by the U.S. to link politics with security issues, security with economic issues, trade with currency policies and, most importantly, Japan with China.

Japan managed to cut off the potentially riskiest area of a linkage between politics and security by having the U.S. commitment to Article 5 of the Japan-U.S. security treaty clearly mentioned in the joint statement by Abe and Trump. The issue will no longer become a bargaining chip in Trump’s “transactional” style of negotiation. This may well have been the most significant success of the summit, since it relieves Japan of the need to practice “supplicant diplomacy” of approaching American leaders time and again in order to confirm U.S. abidance to its obligations set under Article 5.

Regarding the linkage between national security and the economy, the visit to Japan by Defense Secretary Jim Mattis just before the summit enabled Tokyo to establish a security foundational block on the “first floor” of bilateral relations and build economic agreements on the “second floor.”

Given the Trump administration’s protectionist urges, which could be described as its “political libido,” the linkage between trade and currency policy was especially hard for Japan to break. However, a process has been established to contain the exchange rate problems for the moment as the two sides agreed to create a framework for economic dialogue led by Vice President Mike Pence and Deputy Prime Minister and Finance Minister Taro Aso.

The most troublesome linkage of all was that between Trump’s policies toward China and Japan. Abe reportedly stressed to Trump that by withdrawing from the Trans-Pacific Partnership, the U.S. risked forfeiting to China the initiative to make trade rules in the Asia-Pacific region. He went on to explain that, in order to prevent this from happening, the other signatories to the TPP — the TPP 11 — need to maintain the TPP framework and work to ensure that high-level rules and standards agreed on in the course of the TPP negotiations are reflected in the region’s trade and investment rules.

The key question, then, is how the geopolitical and geoeconomic risks brought about by Chinese President Xi Jinping’s “Chinese Dream” vision should be considered. Whether Trump and Abe managed to share a common understanding over this is uncertain.

It does appear that Japan made one miscalculation as it entered the summit. The day before the talks with Abe, Trump and Xi hurriedly held a teleconference. It is believed that the request for the teleconference came from the Chinese side, and it was realized because Trump accepted the request. The Chinese government is said to have approached Jared Kushner (Trump’s son-in-law) in order to hold the teleconference with the president (to be sure, Japan also used the same route in order to secure the Abe-Trump summit.)

When the Obama administration was launched, the Chinese government attempted to use the Chinese spouse of one of Obama’s close relatives as a means of gaining access to the new U.S. president’s inner circle. A highly placed official in the Obama administration once divulged to me that “at a very early stage, China was given notice that we wanted them to stop using family connections to make contact (with the president). Attempting to win over family members is a Chinese specialty.”

There is a danger that the Trump administration will continue to resort to the strategy of linking its approaches to Japan and China. From Trump’s perspective, demonstrating strong ties with Japan increases his leverage vis-a-vis China. And in order to extract concessions from Japan, nothing could work better than the scent of a “huge deal” with China.

There is another linkage that could pose an even graver risk to Japan: Trump could use Japan and the mutual security alliance as leverage with which to secure economic concessions from China. Or in the course of adjusting economic relations with China, Trump might make the kind of transaction that harms Japan-U.S. relations and the security alliance. To avoid this, it is imperative that Tokyo and Washington operate under a closely shared understanding of China.

Japan and the U.S. must share the same understanding of China in order to deal with a number of issues: crisis response on the Korean Peninsula, foreign policy toward Russia, maritime security in the South China Sea, preserving ASEAN integration and security in Southeast Asia, strengthening strategic ties with India and responding to China’s “One Belt, One Road” initiative.

It is inevitable that respective relations among Japan, the U.S. and China will influence each other, and that power that arises from their triangular configuration will affect one another. It will be impossible to fully sever the linkages within this configuration. However, Japan must take utmost care to ensure that any short-term, tactical economic “deals” between the U.S. and China do not disrupt the foundation or necessity of Japan’s long-term strategic diplomatic and security relationships with both the U.S. and China.

Yoichi Funabashi is chairman of the Rebuild Japan Initiative Foundation and former editor-in-chief of the Asahi Shimbun. This is a translation of his column in the monthly Bungei Shunju.