Fantasyland has an interesting core thesis: that every living person in the U.S. is descended from a culture that favored risk and delusion.
Though the concept of "truthiness" or a "post-truth" era has only recently come up, America has a really long history of "the freedom to believe what you want to believe". As such, we have a troubled history when it comes to understanding and believing science.
This first started with Protestantism. When the catholic church started collecting tithe, Protestants rebelled against the idea of paying money to enter heaven. Instead, there was the belief that the bible is what you make of it.
The author makes the claim that in the same way that we have religious fanatics today, this was more or less what the Pilgrims and the Puritans were back in the day.
We started funding people to come across to the new world, and they were primarily fueled by the promise of digging for gold. Ventures would be funded on the basis that they could dig for and return vast quantities of gold back to the old world. The descriptions are hilarious, with "gold likely in the hills". There was no gold, but there was hype.
In some sense, America shows selection bias for people who believe in these crazy dreams of creating a better life. They move to a new place with a ton of risk and not a lot of infrastructure, because they have a dream to do so.
I only made it about 20% of the way through this book, because the ideas seemed to be repeating themselves by that point. I may pick it up once more at a later date.