The short term effect was the testing and evaluating of US Cold War weapons and equipment; most of which of course no longer exist, and/or have long since been replaced. Or, as in the case of the B-52 Stratofortress Bomber, which has been updated and modernized. Cold War jet fighter aircraft used during the Vietnam War, such as the: F-8 Crusader, F-4 Phantom, F-100 Supersabre, F-101 Voodoo, F-102 Delta Dagger, F-104 Starfighter, F-105 Thunderchief, F-111 Aaardvark, A-1 Skyraider, A-4 Skyhawk, A-6 Intruder, A-7 Corsair II, Spy planes U-2 & SR-71 Blackbird, Observation airplanes 0-1 Bird Dog, 0-2 Skymaster, 0V-10 Bronco, Gunship C-130 Spectre, Attack Helicopter Cobra, and Utility Helicopter UH-1 "Huey", were all USED EXTENSIVELY and the performance tested and studied. With the following results: The F-4 Phantom REPLACED all of above listed jet fighter planes, until it itself was phased out by the F-14 Tomcat for the US Navy and the F-15 Eagle for the US Air Force. The B-52 still remains the "King" of the bombers, but is slowly giving way to the B-1 & B-2 bombers. The US Army's Vietnam War attack helicopter "Cobra" was REPLACED by the "Apache" attack helicopter. The US Army's UH-1 "Huey" was replaced by the "Blackhawk" (although UH-1's are still around). The U-2 & SR-71 were retired and replaced by satellites. The U-2 has temporarily been revived for "some" missions. The Observation airplanes were replaced by helicopters.