This month, a team of U.S. Army War College (USAWC) researchers concluded a yearlong study on enterprise-level risk and risk assessment inside the Department of Defense (DoD). At Our Own Peril: DoD Risk and Risk Assessment in a Post-Primacy World argues for a new Department-level risk concept for describing, identifying, assessing, and communicating risk in an environment defined by sudden disruptive change. It suggests that a new concept should rest on four foundational principles: diversity, dynamism, persistent dialogue, and adaptation. Among At Our Own Peril’s many insights, perhaps the most enlightening are those concerning the strategic environment and the complex hazards emerging from it. The report characterizes the contemporary environment as one of “post-primacy,” where the United States remains a global power, but one that is commonly confronted by purposeful and contextual defense-relevant challenges that fall considerably outside of the DoD’s dominant bias and convention.