Short-termism has been the distinguishing intellectual vice of the late twentieth and early twenty-first centuries. For the first time in recorded history, there has been a widespread assumption that the experience of all previous generations is irrelevant to present policy. Institutions, like individuals, however, diminish their effectiveness if they fail to reflect on past successes and failures. The most senior MI5 officer to write some of its history was Anthony Simkins, who after his retirement collaborated with Sir Harry Hinsley in writing the official history of security and intelligence in the Second World War. "I would have been a better DDG," Simkins said afterwards, "if I had written my history first.
Christopher Andrew, The Defence of the Realm