To Guardian readers, the premise of State of the Nation will come as no surprise. A history of British theatre since the war, it makes no mention of theatre in its main title, following Michael Billington’s belief that a nation and its theatre are inseparable. I share that belief, though always with relief that I have never had to defend it. As a theatre reviewer you can get away with slapping a sociopolitically relevant sticker on anything that takes your fancy, and in Billington’s own reviews few four-star recommendations have been awarded without one. In his book, however, he turns his back on that fly-by-night world and retraces his sixty years of theatrical experience so as to put his convictions to the test.