China and the United States are heading toward a war neither wants. The reason, argues Harvard scholar Graham Allison in this razor-sharp analysis, is Thucydides's Trap. This phenomenon, as old as history itself, is named for the Greek historian's assessment of why the Peloponnesian War broke out: a rising power threatened to displace a ruling one. Over the past 500 years, such a struggle has occurred between major powers just sixteen times. In twelve cases, it resulted in war. Today, as an unstoppable China approaches an immovable America, and both Xi Jinping and Donald Trump promise to make their countries 'great again', the seventeenth case looks grim. Unless China scales back its ambitions or the US accepts becoming number two in the Pacific, a trade conflict, cyber attack, or accident at sea could soon escalate. Through uncanny historical parallels, Destined for War shows how close we are to the unthinkable. Yet, stressing that war is not inevitable, Allison also reveals how clashing powers have kept the peace in the past - and what painful steps the US and China can and must take to avoid disaster.