I was reminded what a "recognized historian" named Winston Churchill had to say about this matter, by this post (my own, on another site): http://seekingalpha.com/instablog/399221-tom-au/79016-of-winston-churchill-s-contribution-to-the-modern-postwar-world
Key quote: "If we fail, the whole world, including the United States, including all that we have known and cared for, will fall into the abyss of a New Dark Age, made more sinister, and perhaps more protracted, by the light of perverted science."
Like the proverbial "Dutch boy with his finger in the dike," Churchill made sure that Britain did not "fail." It's possible that someone else would have done almost as well, but there was a real possibility of Britain's "failure" (and the above, attendant consequences), under another leader. Unlike Churchill's work, my own piece outlines two "failure" scenarios, one of which was much more likely to lead to a "New Dark Age" than the other.
Besides being Prime Minister of Britain, Churchill also published "A History of the English-Speaking Peoples," and a four volume series on "The Second World War." Given who else he was, the latter was practically "auto biographical."