Insignia
The division was nicknamed "Old Ironsides", by its first commander, Major General Bruce R. Magruder, after he saw a picture of the frigate USS Constitution, which is also nicknamed "Old Ironsides". The large "1" at the top represents the numerical designation of the division, and the insignia is used as a basis for most other sub-unit insignias. The cannon represents fire power, the track represents mobility, and the lighting bolt represents speed and shock force.
The three colors, red, yellow, and blue represent the Artillery, Cavalry, and Infantry Branches respectively, which are the colors of the three original combat arms which, when forged into one, created the field of Armor. This "pyramid of power" was devised by the order of then-Lieutenant Col. George S. Patton, Jr. in Bourg, France in early 1918 during Patton's formation and training of the Tank Corps in support of the American Expeditionary Force under General John J. Pershing.
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