Viewed from Brussels, China’s importance to the world’s security and economic systems has never been greater. Viewed from Beijing, the European Union’s importance has rarely been smaller.

This imbalance will be on display in Prague on May 20, when EU and Chinese leaders get together for a summit. The meeting should have been held last December, but in an imperious gesture the Chinese cancelled it after Nicolas Sarkozy, France’s president, showed “disrespect” by arranging talks with the Dalai Lama, Tibet’s exiled spiritual leader.