“It’s about reacting to bad circumstances in the worst possible way,” he writes in the book. “It’s about a culture that increasingly encourages social decay instead of counteracting it.”

In the episode, I’m joined by my colleagues Nick Confessore and Nate Cohn, who discuss the shake-up in Mr. Trump’s campaign, which seems to confirm his almost singular focus on white, economically insecure voters. We also discuss whether that segment of the electorate can really put him in the White House.

Please let us know what you think of the show. You can reach us at therunup@nytimes.com, or find me on Twitter, and you can leave ratings and feedback on iTunes.

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