I am a fan of P J O'Rourke's writing and sympathetic to his libertarian stance. Never having read Adam Smith's Wealth of Nations, I thought I could take a short cut by reading this. Overall I am not sure that I have achieved my original objective.
You are likely to be interested in economics to want to read either Wealth of Nations or P J O'Rourke. The rest of this review is written on that assumption.
Overall, the book is untidily written (particularly the first chapter) and for the non-USA reader, some of the references seem beyond obscure. The author fails to avoid getting between you and the subject matter. At times (thought not always) it is unclear whether we are reading about Adam Smith's opinions regarding economics or those of the author.
Which is not to say that the book is without merit, I think I know more about the topic than I did, P J O'Rourke's comment is often funny, it just doesn't obviously meet the objective of reading one into "Wealth of Nations"