WASHINGTON/BEIJING -- When a rising power challenges a ruling power -- as Athens did with Sparta in ancient Greece, or as Germany did with Britain a century ago -- most such contests have ended badly, often for both sides.
Twelve of the 16 cases over the past 500 years have resulted in war, according to American political scientist Graham Allison. Whether the U.S. and China can avoid the so-called Thucydides trap, as Allison framed it, looks to be the preeminent geopolitical question of our time.
