Ireland's air facilities are regularly used by the United States military for the transit of military personnel overseas, mainly to the Middle East. The Irish government began supplying military and civilian air facilities in Ireland for use by the armed forces of the United States during the 1991 First Gulf War. Following the September 11 attacks in 2001, the Irish government offered the use of Irish airspace and airports to the US military in support of the War in Afghanistan and the 2003 invasion of Iraq, on the condition that aircraft be unarmed, with no cargo of arms, ammunition or explosives, not engage in intelligence gathering, and that the flights in question do not form part of military exercises or operations at the time. Casement Aerodrome, Baldonnel (military) and Shannon Airport (civil), used as stopover hubs, have seen more than 2.4 million American troops pass through from 2002 to 2014. An average of more than 500 US troops passed through Shannon every day during that period.