Operation Gladio by the dissolution of the French stay-behind paramilitary movements. Historian Daniele Ganser claims that: Next to the CPC, a second secret army command center, labeled Allied Clandestine Committee (ACC), was set up in 1957 on the orders of NATO's Supreme Allied Commander in Europe (SACEUR). This military structure provided for significant US leverage over the secret stay-behind networks in Western Europe as the SACEUR, throughout NATO's history, has traditionally been a US General who reports to the Pentagon in Washington and is based in NATO's Supreme Headquarters Allied Powers Europe (SHAPE) in Mons, Belgium. The ACC's duties included elaborating on
Supreme Headquarters Allied Expeditionary Force with the American 6th Army Group (6 AG) under the command of Lieutenant General Jacob L. Devers. During the invasion of southern France, the 6 AG was under the command of the Allied Forces Headquarters (AFHQ) of the Mediterranean Theatre of Operations, but after one month command passed to SHAEF. By this time, the three Army Groups had taken up the positions on the Western Front in which they would remain until the end of the war—the British 21 AG to the North, the American 12 AG in the middle and the 6 AG to the South. By December 1944,