These captured American aircraft have a particularly timeless quality to them. Some of them remain in daily use, such as the UH-1 Huey helicopter. The others, the F-5 Tiger and A-37 Dragonfly, though less familiar, still register, as both remain in service in several air forces. On display at Saigon’s War Remnants Museum, they’re relics of the last time the United States was officially defeated in combat. At least that’s the idea in showing them off, as reminders of the one-time limits of US power.