The I and II Air Support Commands were specifically directed to develop appropriate exercises in cooperation with Army ground infantry and armored units. Light and Medium bombardment, fighter, and observation units, after completing their regular training, were assigned when possible to one of these commands for the desired combined training before deployment overseas. The results of this training became evident after the D-Day landings in France; the Italian Campaign and in the Pacific, the New Guinea campaign; the Philippines Campaign, and the Battle of Okinawa.