Alan Turing, while undoubtedly vital to the war effort, was only part of equation. It was Tommy Flowers that designed and built Colossus, buying the components with his own money because TPTB didn’t believe that valves would be reliable enough. The Bombe, Turing’s design, was a single purpose electro mechanical computer, whereas Colossus was electronic and programmable and is considered as the first electronic programmable computer