Next month, for the first time since 2011, a Japanese leader will make an official visit to China. These two Asian giants have one of the world’s largest trading partnerships, yet their relationship is marked by historical tensions and petty snubs. Seven years ago, the trip to Beijing by former Japanese prime minister Yoshihiko Noda lasted just twenty-one hours, and he was not granted a meeting with Xi Jinping, who was soon to become China’s leader.

But the two countries, whose relationship is crucial to the region’s stability, are suddenly finding common ground. At a recent meeting in Vladivostok in Russia, Xi told Shinzō Abe, who was last week re-elected as head of Japan’s ruling party, that their nations should together lead the world towards an open economy. They are considering a free trade deal, in partnership with South Korea, and are looking to cooperate on infrastructure projects as part of China’s Belt and Road Initiative.

For countries such as Australia, which have much to gain from easing tensions across Asia, the question is whether the Japan–China thaw will extend beyond economics and trade.

To appreciate the extent of this turnaround, it is worth recalling the last time the two nations’ leaders met in Vladivostok. The infamous encounter took place during the height of tensions in 2012 over the control of five small, uninhabited islands in the East China Sea, known to the Japanese as the Senkaku and to the Chinese as the Diaoyu. Japan’s Noda and China’s Hu Jintao began with niceties but soon stood inches apart, scowling as Jintao warned of the consequences of Japanese assertions of sovereignty over the islands. It was, as Richard McGregor recounts in his book Asia’s Reckoning, “one of the most astounding meetings ever between a Chinese and a Japanese leader”.

Yet relations have changed. China has stopped making hundreds of anti-Japan films each year, and the countries have stopped summoning each other’s ambassadors for two a.m. dressings down. Trade declined from 2012 but last year recorded an increase.

This apparent thaw has been widely credited to the protectionist stance of Donald Trump, who launched a trade war against China and is threatening to impose crippling tariffs on Japanese car exports. Trump has, unintentionally, succeeded in pushing these two enemies closer together.

The main sources of tension between the two nations have not disappeared. For instance, Abe continues to send controversial ritual offerings to the Yasukuni Shrine in Tokyo, which honours convicted war criminals who oversaw Japan’s brutal invasions of China and South Korea. And Japan continues to signal that it mistrusts China’s military expansion and will resist Chinese assertions of power. Japan’s annual defence blueprint in August warned of the risk of China’s growing military power – an assertion that Beijing described as “extremely irresponsible”. Earlier this month, a Japanese submarine participated for the first time in an anti-submarine warfare exercise in the South China Sea. The drill did not take place near China’s various island bases, but it prompted a warning from Beijing to “act cautiously”.

Abe has also gone to occasionally ridiculous lengths to demonstrate that he wants the United States to remain committed to the region. He has tried hard to develop close relations with Trump, attempting awkward fist bumps and famously giving the president a golden US$3755 golf club after the 2016 US election. 

But Trump’s tariffs, which have made Tokyo and Beijing joint champions of free trade, will likely lead to closer political and diplomatic ties. Xi and Abe have now met regularly, as have senior officials from both nations. This has led to cooperation in areas outside economics, such as the resumption of military exchanges.

Importantly, Trump’s affront to his old allies in the region extends beyond trade. Japan is worried about Trump’s approach to North Korea, which could destabilise the region and occurred with minimal consultation with Tokyo or Seoul. Trump has also repeatedly insisted that Japan must pay more for the security blanket that the United States provides.

Japan is not about to abandon or damage its alliance with the United States to improve ties with China. But, like Australia, it is facing choices and questions about its relationships in the region that have not arisen since World War II. This will sometimes involve overhauling longstanding conventions. A new approach to its relationship with China, handled delicately, marks progress, even if the promise of closer ties is also a sign of Trump’s willingness to wreak havoc on the existing regional order.