Back in the heyday of the Cold War, the United States Air Force and Lockheed’s Skunk Works had a plan to turn the legendary Mach 3+ SR-71 Blackbird into a supersonic nuclear bomber capable of penetrating deep into Soviet airspace to deliver nuclear payloads with minimal chances of intercept. The program, as you probably know, never made it into production… but you might be surprised at just how close it came.