Kicking off our annual What the Hell’s summer book series, Zach Cooper discusses his new book, Tides of Fortune: The Rise and Decline of Great Militaries (Yale University Press, 2025). How will the United States and China evolve militarily in the years ahead? Many experts believe the answer to this question is largely unknowable. But in his book, Zack Cooper argues that the American and Chinese militaries are following a well-trodden path. For centuries, the world’s most powerful militaries have adhered to a remarkably consistent pattern of behavior, determined largely by their leaders’ perceptions of relative power shifts. WTH is China on this path? And importantly, WTH is the US?

Zack Cooper is a senior fellow at the American Enterprise Institute, where he studies US strategy in Asia, including alliance dynamics and US-China competition. He also teaches at Princeton University and serves as chair of the board of the Open Technology Fund. Before joining AEI, Dr. Cooper was the senior fellow for Asian security at the Center for Strategic and International Studies (CSIS).

Find Tides of Fortune: The Rise and Fall of Great Militaries here.

Find the transcript here.