Thanks for the review. I haven't read the book, but from what you've said it sounds like he's saying that if we don't start taxing wealth, then the rich will become more and more powerful, until they rule over everyone else.
This is pretty similar to what Thomas Piketty argues in Capital in the Twenty-First Century, though. I'll have to check out the book.
RE: Niall Ferguson's book "The House of Rothschild"