In 2011, during President Barack Obama’s first term, then-Secretary of State Hillary Clinton announced a momentous new policy: America would “pivot to Asia.” At home, the pivot was primarily appreciated more for what it was turning away from: the Middle East. But in Beijing the strategy, which focused on relocating U.S. naval assets in the Pacific, signaled America’s determination to contain a rising China.

Steadily, if little by little, the White House’s grand strategy began to change. About a year after it had been announced,...