My comparison review that won Reader's Choice Award for SlaterStarCodex 2021 Book Review Context
I think Zeihan is right to discount the idea of a united Eurasia. Transport by water is far cheaper than transport by land and crosses far fewer borders of taxing authorities. Getting bulk cargo from China to Europe by land is incredibly expensive (as evidenced by the fact that nobody does it). For all practical purposes, America is much closer to Europe than China or India.