What term describes a defense without an exposed flank, consisting of forces deployed along the outermost portions of the defended area?

The term that accurately describes a defense without an exposed flank, consisting of forces deployed along the outermost portions of the defended area, is referred to as a Defense Perimeter. This concept emphasizes the strategic positioning of defensive forces in a way that creates a solid and continuous line around a designated area, minimizing vulnerabilities and effectively covering all approaches. The design of a Defense Perimeter is critical in military strategy as it helps to protect key assets and personnel from enemy advances by ensuring that there are no gaps in the defensive line.

In contrast, the other options represent different aspects of defense but do not convey the same meaning. "Outer Defense" might imply forces positioned at the edges, but lacks the specific connotation of being a comprehensive barrier like a Defense Perimeter. Similarly, "Defense Line" typically suggests a linear arrangement but does not necessarily indicate a surrounding configuration, and "Defense Zone" may refer to a broader area of control rather than the specific arrangement of forces around an area. Thus, the terminology of Defense Perimeter encapsulates both the strategic depth and coverage required in effective defensive operations.