This is without a doubt the best book I've read this year, if not ever.
Caplan delivers spectacularly on the title. Not only is it a rebuttal of the common view of economists that everyone always acts rationally, but it also strongly argues that humans are _particularly bad_ in the political arena. The book persuasively challenges many common criticisms of democracy: that most voters are stupid and only vote in self-interest, that bureaucratic inefficiencies are a bad thing, that politicians are mostly crooked, that low-voter turnout is a bad thing, and that democracies aren't very good at giving the people what they ask for.
MY GOOD IS THIS BOOK GOOD.
If you accept Caplan's premise, and evidently I do, the consequences he points out are staggering. "Get out and vote" campaigns are actively harmful to society. If you're running for office, you should in fact not keep your campaign promises. It's a delightfully different lens for looking at the world, and one which puts a lot more into perspective than I realized beforehand.