Supreme Headquarters Allied Powers Europe Command Operations has at its disposal standing forces such as: Airlift support for SACEUR's travels is provided by the USAF's 309th Airlift Squadron at Chièvres Air Base, Belgium. In 2012 and 2013, NATO underwent a reorganization of the military command, and the land component commands at Heidelberg and Madrid were deactivated, the maritime component command at Naples was closed and the air component command at Izmir also shut down. Today Allied Command Operations (ACO) is one of the two strategic commands of NATO (the other being Allied Command Transformation (ACT). Under this structure, there are two joint force operational headquarters
Western Union (alliance) transferred to the newly established North Atlantic Treaty Organisation (NATO), providing the nucleus of NATO's command structure at the Supreme Headquarters Allied Powers Europe (SHAPE). As a consequence of the failure of the European Defence Community in 1954, the London and Paris Conferences led to the Modified Treaty of Brussels (MTB) through which the Western Union was transformed into the Western European Union (WEU) and was joined by Italy and West Germany. As the WEU's functions were transferred to the European Union's (EU) European Security and Defence Policy (ESDP) at the turn of the 21st century, the Western Union is