There is a time at which the tides of history change. There is a time at which the nation–state suddenly becomes cognizant that a discontinuity with the past has occurred, that its long anticipated place among countries has been irrevocably altered, that its prior assumptions about role, status, and security have been proven wrong. This is the existential interval in which a government is vulnerable to entanglement in the most major wars. This existential interval is the critical point on the state power cycle.

The next three chapters weave conceptual and theoretical argument with historical evidence and empirical findings to develop the power cycle theory of major war and systems transformation. To emphasize generality, we begin at the theoretical level. Chapter 5 ties each aspect of theory to the real problems confronting statesmen, and their specific responses to them, in the early years of the twentieth century. As a prelude, we here include statements of the period which express something of the uncertainty and tumult felt at a time of monumental critical changes in the trend of history for all the leading states.

“The future belongs to Russia, which is growing and growing and is becoming an ever-increasing nightmare for us.” The German Foreign Minister, long haunted by this reality, finally confronted it in August 1914 (Wohlforth 1987, p. 362). Awareness of the changing tide of German power was expressed in Berlin by profound angst.