When the leaders of the Quad were meeting in Tokyo on May 24, China and Russia jointly flew six strategic bombers near Japan in a show of force.
But while Russia wanted to be even more aggressive, sending ships through Japan's chokepoints like the two countries did last year, China was hesitant to do so, sources say.
Until 2021, it was the Chinese side that was more eager to team up with Russia. But Moscow's struggles in Ukraine have changed the dynamics. Beijing does not want the international community to conclude that it is united militarily with Russia.
China's supply chains, linking it with Japan, the U.S. and Europe, are its economic lifelines. As the world's second-largest economy, China has no business sinking alongside Russia.
Heading into the Chinese Communist Party's quinquennial National Congress in autumn, Chinese President Xi Jinping needs to at least temporarily stabilize relations with the U.S.
Going forward, all eyes will be on the frequency and scale of Chinese and Russian joint military activities around Japan. It will provide important clues about China's path.
Read this week's China Up Close by Katsuji Nakazawa here.