Darren Waterworth's review is absolutely right. I can't improve on what he has already said about this book, so I'd only add this.
Maybe it's nostalgia, but it seems to me that in my youth political figures were larger than life - "they don't make them like that any more." This can't be just because they didn't have to appear on television - my recollection is that they had to appear on the radio, and that they had to demonstrate that they could talk about more than just the political issues of the day.
Nor can it be because they were not subjected to an intrusive scrutiny by a hostile Press - as the book brings out, Bevan had first to distance himself from Beaverbrook, who tried to buy him, and then to spend years portrayed as the hate-figure on the Left, before miraculously being translated into a revered elder statesman, the inheritance of whose broad-church "mantle" was for years the objective of every subsequent Labour leader.
During the war, Bevan was up against Churchill, and the book brings out how surprisingly well-matched as orators they were (and that both of them had overcome speech impediments to become so). The fact remains that (as it turned out) Bevan was "barking up the wrong tree" all his life, and yet the absence of figures like him has made our present politics much the poorer. It pays to be reminded of this - perhaps it's the reason politicians today are generally held in such contempt.