A Summary History of the 4th Infantry Division, whose motto is "Steadfast and Loyal," is a heavy mechanized division in the United States Regular Army. The 4th ID has a storied history from WWI, WWII, Vietnam, and Operation Iraqi Freedom. Arguably the most modernized division in the army, the 4ID is currently organized with four Brigade Combat Teams (BCT), a fires brigade, an aviation brigade, and various supporting units.