It flared up over plans to mark the battle's 250th anniversary with a re-enactment, and ended with Quebec separatists crying victory and Canada's federal government beating ahastyretreat.
"Downing Street suddenly knew that it faced a choice between the story coming out, though in a far more technicolour and dramatic way than anyone had up to that stage realised, or beating ahastyretreat, " he writes in the latest edition of the magazine, edited by Tory MP Boris Johnson.