Chinese President Xi Jinping’s invocation of the “Thucydides trap” at his summit meeting with US President Donald Trump is a carefully chosen warning about the central strategic question of the 21st century -- can an established superpower and a rising challenger avoid sliding into war? As the two leaders met in Beijing for the first time in seven years, amid trade disputes, Taiwan tensions, technology rivalry and war in the Middle East, Xi said, “The whole world is watching our meeting.”
