The 11th Armored Cavalry Regiment ("Blackhorse Regiment") is a unit of the United States Army garrisoned at the Fort Irwin National Training Center in California. Although termed an armored cavalry regiment, it is being re-organized as a multi-component heavy brigade combat team. The regiment has served in the Philippine–American War, the Pancho Villa Expedition, World War II, the Vietnam War, Gulf War and Iraq War. The 11th ACR serves as the opposing force (OPFOR) for the Army and Marine task forces, and foreign military forces that train at Fort Irwin. The OPFOR trained U.S. Army forces in mechanized desert warfare following a Soviet-era style threat until June 2002, when the OPFOR and the 11th Armored Cavalry Regiment changed to portraying an urban/asymmetrical warfare style of combat U.S. soldiers are facing in operations abroad. From June to December 2003, members of the 11th ACR deployed to Afghanistan, where they helped to develop and train the armor and mechanized infantry battalions of the Afghan National Army. These specialized units would defend the Afghan capital during the country's constitutional convention. In January 2004, the 11th ACR deployed to Iraq. The 11th ACR was not reorganized under the U.S. Army Combat Arms Regimental System, but has been reorganized under the U.S. Army Regimental System. History 11th Cavalry Regiment The regiment was constituted on 2 February 1901 in the Regular Army as the 11th Cavalry Regiment, and was organized on 11 March 1901 at Fort Myer, Virginia. The regiment participated in the 1916 Pancho Villa Expedition under the command of William Jones Nicholson. For an operational history of the regiment, see the separate squadron histories below. At the start of World War II, the 11th Cavalry was stationed at the Presidio of Monterey in California. They moved to Fort Ord in stages from 16 to 27 January 1940 and again to Camp Clayton on 15 April to 15 May 1940 for temporary training. They participated in maneuvers at Fort Lewis in Washington from 4 to 29 August 1940, and returned to the Presidio of Monterey on 31 August 1940, where they were detached from the 2nd Cavalry Division, and resumed its status as a separate regiment. They next moved to Camp Seeley in California on 7 November 1941, and again to Live Oaks, California on 24 July 1941; they then returned to Camp Seeley on 17 September 1941, and to Camp Lockett on 10 December