US Army soldiers inspect MIM-23B Hawk surface-to-air missiles in 1977.HUM Images/Universal Images Group via Getty ImagesUkraine is operating US-made Hawk air-defense systems from the 1960s.Though the US retired these tools decades ago, Kyiv is now using them to kill Russian missiles.One Ukrainian operator recently praised the effectiveness of the antiquated system.The Ukrainians are using an American-made air-defense system that the US retired from service more than two decades ago to successfully shoot down Russian cruise missiles.The MIM-23 Hawk is a medium-range, surface-to-air system that was first fielded in the 1960s and has long been considered obsolete, with militaries favoring more portable systems.