The Evolution of US Army Doctrine as a Learning Process

U.S. Army doctrine emerges here as an institutional learning cycle in which combat experience, alliances, and organizational reforms continually reshape how the Army thinks about and conducts operations—from the Continental Army to today’s Multi-Domain Operations. Early patterns of combined arms and joint/coalition cooperation appear at Yorktown, where infantry, engineers, and artillery worked with French ground forces and a naval blockade, and the Civil War is framed as an early form of what would now be called multi-domain integration, including naval-ground cooperation and even limited air employment (balloons).

A shift from ad hoc manuals to a more disciplined doctrinal enterprise begins in 1896 with War Department numbered publications, culminating in the 1905 Field Service Regulations as a foundational combined-arms manual—still dominated by tactics, techniques, procedures, and logistics rather than strategy or joint operations. World War I then produces an unprecedented surge of lessons-learned documents (including U.S., British, and French materials), much of which informs the 1923 Field Regulations, while the interwar period sees far fewer publications. In World War II, systematic collection and dissemination of lessons expands again, with after-action review methods advanced by S. L. A. Marshall; FM 100-5 evolves through 1944, 1949, and 1954, with the 1962 edition notably broadening scope to strategy, the spectrum of war, and joint/combined operations. The 1976 FM 100-5 reflects analysis of the 1973 Yom Kippur War, focuses on NATO/central Europe, and introduces “Active Defense” as a named approach to operations.

Four enduring accelerants of doctrinal evolution then stand out: multi-service doctrine (ALFA to ALSA/ALSSA), multinational doctrine through NATO standards and coalition handbooks, the rise of true joint doctrine after the 1986 DoD Reorganization Act, and institutionalized lessons learned via the National Training Center and the Center for Army Lessons Learned. Doctrinal architecture is also reorganized into a hierarchy (ADP/ADRP, FM, ATP) and clarified against “concepts” that drive experimentation and DOTMLPF change. This trajectory points to Multi-Domain Operations as the contemporary operational concept—combined-arms employment integrating joint and Army capabilities through improved C2 networks, mission command, and deeper cross-domain synchronization across the full range of operations.

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