This book is nominally about Chamberlain, but we see a lot of Churchill and Charmley tries to bring in his arch-villain whenever possible. This visceral dislike for Churchill - combined with a fawning admiration for Chamberlain - is troubling in that it prevents Charmley from acknowledging that one was ever right and that the other was ever wrong. This book is about as partisan as possible.
His ultimate argument, that Nazi Germany posed no threat to Britain is absurd. Charmley does not even bother to examine Hitler's ambitions; had he done so, his argument would have fallen apart. Germany sought to be an Atlantic power, as well as a European power. Ideological bias blinds Charmley from the fact that a triumphant Germany would have effectively emasculated Britain and encouraged Italy and Japan to poach London's colonial possessions. He despises America enough to blind him to the fact that there were far more rapacious powers operating in the 1940s (see some of the letters Charmley has written to the Daily Telegraph)
All in all, this book is best read as an example of modern-day Tory cynicism and contempt for the past. As a chronicle of the years before the war it has little to recommend it.