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.
Thanks for your comment!
No, Ferguson is rather descriptive in his book. He doesn't (morally) evaluate the richness of the Rothschilds.
As the Rothschilds today are no longer very powerful, one could make the case against taxing wealth (at least against taxing wealth with the aim to stop the rich getting richer).