In a book of essays called “The Next Great War?”, which examines Sino-American relations through the lens of the first world war, Richard Rosecrance warns of “the tyranny of small things”, the points of friction and misunderstanding between rival powers that, without leadership to manage them, can lead to conflict. China and America today are not about to take up arms, but small things are rapidly accumulating. The two distrust each other more now than at any point since Richard Nixon went to China almost 50 years ago. As a presidential election draws near, the potential for dangerous miscalculation is growing.