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Army Combat Branches: Infantry

Army Combat Branches: Infantry. The infantry is the oldest and most important of the U.S. Army's combat arms. Its insignia consists of crossed muskets, Model 1795; its motto is “Follow Me.” Its primary mission is to close with and destroy or capture the enemy.

The infantry does not fight alone. It often fights with, sometimes supports, but more frequently is supported by the army's other arms and services, and by the air force, the navy, and the Marine Corps.

Although the infantryman can arrive on a battlefield in a variety of ways, he is always a ground combat soldier, who fights on foot with the weapons and ammunition he can carry. He can fight from armored vehicles when the situation demands. His basic weapon is the rifle and bayonet, although he has used grenades and grenade launchers, machine guns, mortars, flamethrowers, and some hand‐ held antitank weapons to bolster his combat effectiveness.

On 14 June 1775, the Second Continental Congress authorized the raising of ten companies of riflemen to be part of George Washington's new Continental Army besieging Boston at the outset of the Revolutionary War. There, these companies were grouped into regiments, an organization that for the next 181 years remained the infantry's primary tactical and administrative unit.

Over time, the regimental structure underwent several changes. Until the Spanish‐American War, infantry regiments consisted of ten companies grouped under one headquarters. In 1898, each regiment was given two battalions, each battalion consisting of four companies. The battalion then became the primary tactical organization while the regiment retained administrative and tactical oversight functions.

When the United States entered World War I in 1917, the number of battalions in each regiment was increased to three, each battalion still containing four companies. This remained the standard regimental structure until 1956, when the entire regimental structure was done away with, to be replaced by the Pentomic battle group—a unit smaller than a regiment but larger than a battalion. The army's leaders had become convinced that a different type of unit was needed to meet the demands posed by growing nuclear weapons and chemical warfare threats.

The Pentomic structure lasted only a few years; in 1961, a new organizational concept was introduced: Reorganization Objective Army Division (ROAD). ROAD eliminated the infantry battle group and brought back the battalion, but not the regiment, as the infantry's primary tactical and administrative organization, a position it still holds. Despite the U.S. Army's attempts to perpetuate regimental traditions, honors, and lineages through the Combat Arms Regimental System (CARS), the infantry community has never fully recovered from the loss of the regiment, the traditional key unit in the British army and many other forces.

Various types of infantry units have been developed over the years to permit the American infantry better to accomplish its mission in various parts of the world and on differing types of terrain, among these specialized forms of infantry are the following: light, airborne, air assault, mechanized, and ranger. In the process, the infantry has become the most mobile and flexible of the army's combat arms.

Despite furnishing the bulk of the United States's men and suffering by far the greatest number of battle casualties, infantry service, at least until World War II, was never considered choice military duty. U.S. Military Academy graduates, for example, invariably chose the U.S. Army Corps of Engineers, the cavalry, or the artillery before the infantry. Even today, service with line infantry units is not considered choice duty. Service with airborne or ranger infantry units, though, is deemed necessary for infantry officers who hope to reach flag rank.

As a result of this attitude, after years of struggle, the infantry was finally given its own home base and training school at Fort Benning, Georgia, in 1918. Until then, infantry officers and noncommissioned officers were given special training, if at all, at other service schools or on the fields of battle.

Many outstanding U.S. military leaders and warriors have come from the infantry's ranks, Robert Rogers, George Washington, Joshua Chamberlain, Nelson Miles, Alvin York, Audie Murphy, George C. Marshall, and Dwight D. Eisenhower among them.

Despite the technological advances that have marked the army's progress in recent years, the role of the infantryman on the future battlefield will not change but will remain as important to future success as it has been in the past.
[See also Army, U.S.; Land Warfare; Side Arms, Standard Infantry; Tactics.]


John K. Mahon and and Romana Danysh , Army Lineage Series, Infantry, Part I: Regular Army, 1972.
The Department of the Army Manual, December 1980, Section V, pp. 6–19.
Gregory J. W. Urwin , The United States Infantry: An Illustrated History, 1775–1918, 1988.

Albert N. Garland

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