The question of when — not whether — China might attempt military action against Taiwan has become the organizing analytical question of western Pacific security. It is asked because Chinese leaders, most explicitly Xi Jinping, have provided a series of statements and deadlines that create at least a public framework for reading Chinese intentions. That framework is ambiguous enough that analysts reach different conclusions from the same data, which is itself informative: ambiguity about the timeline is probably a feature of Chinese strategy rather than a gap in its communication.