In his preface Robert Blake writes, 'The title of this book is taken from a remark attributed to Asquith after he had attended Bonar Law's funeral in Westminster Abbey. ''It is fitting, '' he is reputed to have said, ''that we should have buried the Unknown Prime Minister by the side of the Unknown Soldier.'' I have used this phrase, not because I consider that Asquith's remark was either just or true, but because, however unfairly, it has come to...