The Mitsubishi Zero lightweight dogfighter was replaced by heavier, expensive aircraft, like the Grumman Hellcat, early in World War II.
By the 1960s, big, heavy fighters with radar guided air-to-air missiles replace outmoded dogfighters; faced with the MiG 21 in Vietnam, the U.S. Air Force gives lightweight fighters a second look.
Early in World War II, the Mitsubishi Zero shows the viability of lightweight fighters; heavier and more expensive aircraft, like the Grumman Hellcat, topple the Zero and diminish the stature of lightweight fighters in the eyes of military planners.