The prospect of United States, Chinese and Russian leaders meeting at the Asia-Pacific Economic Cooperation (Apec) summit in Shenzhen this November has revived the Yalta analogy. Talk of a Trump-Xi-Putin summit – echoing the 1945 meeting that reshaped the world – surfaced during the first Trump term, and speculation returned last year with the 80th anniversary of the second world war. No such meeting occurred. However, Chinese President Xi Jinping hosted the two presidents back-to-back in...