As China’s leader, Xi Jinping, laid out his priorities this past week for a breakthrough third term in power, officials parsed his words for signs of where the country was headed. What he did not say was as revealing.

The omission of two phrases from his key report to a Communist Party congress exposed his anxieties about an increasingly volatile world where the United States is contesting China’s ascent as an authoritarian superpower.

For two decades, successive Chinese leaders have declared at the congress that the country was in a "period of important strategic opportunity,” implying that China faced no imminent risk of major conflict and could focus more on economic growth.