I think Chamberlain was misaligned in history. He did the best with the tools and facts he had at the time. He really had little choice when Germany annexed Czechoslovakia. He was honestly hoping this appeasement would be his last. If it was the last, he might have been regarded as a diplomatic hero.

As this article suggests, by doing everything possible to avoid war, the UK was fairly united when it become obvious there was war. In this senses, Chamberlain seems like a genius.