The inherent uncertainty of war, when combined with exertion, danger, and chance, produces an ever-present friction. The commander's role throughout military history has been to reduce the uncertainties of war for his own side and increase them for his enemy. Notwithstanding great advances in the arts and sciences of command and control, the best commanders have traditionally used trusted subordinates as extensions of their own minds as a way of penetrating the fog of war. This technique has come to be called the "directed telescope." "The Directed Telescope: A Traditional Element of Effective Command" examines the historic role played by liaison officers, aides-de-camp, and staff observers as extensions of the commander. The study focuses on the relationship between several great commanders and their liaison officers, as well as the systems, techniques, and organizations they employed. With this study in hand, modern-and future-commanders can draw on an expert analysis of various command and control expedients as they create new versions of the directed telescope.

Introduction / The pre-nineteenth-century era / The Napoleonic era / The modern era. The American Civil War -- World War I -- The interwar years -- World War II -- Post-World War II / Conclusions.