There are many more such "problem solvers", some of them colourful individuals like Lieutenant-Colonel Stewart Blacker, "interested in blowing things up" since boyhood, who devised the Hedgehog, a grenade launcher that did for nearly 50 U-boats.

Mostly these success stories are broad team efforts, involving individuals and instititutions both civil and military. In the case of the Mustang, Harker's intuition was backed by the science of a Polish mathematician turned engineer, Witold Challier, the bureaucratic muscle of Air Chief Marshal Sir Wilfred Freeman and the diplomatic interventions of the US ambassador to Britain John "Gil" Winant and his polo-playing assistant air attaché Tommy Hitchcock (allegedly the inspiration for two Scott Fizgerald characters). And of course nothing could have happened if there had not been a superb powerplant — the Rolls-Royce Merlin engine — to drop into the airframe. 

The narratives often follow traditional lines, with the heroes having to battle with vested interests and institutional obtuseness before the final triumph. They, and the themes and ideas they support, are presented in a bustling, enthusiastic style and the professor's lectures at Yale must be a lot of fun. He has an open-minded approach to sources and this book contains what I think is a notable first. In the acknowledgements, the author pays tribute to Wikipedia. Historians tend to be rather sniffy about the online encyclopedia. Kennedy admits to being "mightily impressed" by some of the lengthy and scholarly anonymous entries and cites them in the notes. Recognition of the quality and value of much Wikipedia content is overdue and those of us who use it should give proper credit — as well as putting our hands in our pockets.

Kennedy says at the outset that this is a new treatment of the Second World War, but not an attempt to reinterpret it. The "engineers" aren't being given all the credit for final victory — they just helped it mightily along. War stimulates innovation. It was much easier to be an innovator in a Western democracy than it was under Nazism or Communism, where any display of free-thinking was potentially dangerous. It's no surprise then that most of Kennedy's material comes from the Anglo-American side of the fence.