The recent summit meeting between President Donald Trump and Chinese President Xi Jinping appears to have concluded without any significant agreement on any of the many disputes dividing the two countries. That should not worry observers. It merely shows that both sides are still circling one another like sumo wrestlers, watching the other closely to try and find a weakness to exploit.

Summits like this used to be a common feature of the Cold War. Every nation knew there were two superpowers vying for global dominance: the United States and the Soviet Union. When the heads of state (or political leaders, as the real power in the Soviet Union often rested with the premier rather than the president) met, all knew that the two represented two strong, near equal powers.