 However, the unit also had regular military exercises that kept up proficiency and in gunnery and bombing contests they would often score at least as well or better than active-duty USAF units, given the fact that most ANG pilots were World War II combat veterans.With the surprise invasion of South Korea on 25 June 1950, and the regular military's complete lack of readiness, most of the Air National Guard was federalized placed on active duty.The 139th was retained by the State of New York to maintain the air defense mission.