Which of the following is NOT one of the enduring functions of the US Navy?

The enduring functions of the US Navy traditionally include roles that are fundamental to maintaining maritime security and operational effectiveness. Among these, deterrence, power projection, and sea control are crucial components of naval strategy. Deterrence refers to the ability to prevent conflict through the demonstration of military capability and resolve; power projection involves the capacity to deploy and sustain forces in various regions to influence events and achieve national objectives; and sea control is the ability to ensure comprehensive access to maritime areas, enabling friendly operations while denying access to adversaries.

In contrast, cyber defense, while increasingly vital in modern military operations, is not classified as one of the Navy’s traditional enduring functions. This domain primarily involves protecting information networks, systems, and infrastructures from cyber threats and attacks and is a relatively newer focus in military strategy, reflecting the evolving nature of warfare.

Each of the other options embodies long-established naval missions that have been recognized for decades, emphasizing physical presence and dominance on the seas, while cyber defense represents an essential, but more contemporary, aspect of military capability rather than a historical function of naval operations.