I’m an American baby boomer. For me – and I suspect many others of my generation – China’s image has not been the best. In my mental collage, fascination with Chinese culture and invention is offset by wariness of China’s political system and potential power. Some parts of the collage: as a boy, listening to stories told by a Korean War vet uncle and neighbors about hand-to-hand fighting with young Chinese soldiers wearing tennis shoes on their frozen feet at Chosin Reservoir; as a teen, accounts of Mao Zedong’s chaotic Cultural Revolution, its purges and Red Guards; in middle age,...