1) Piketty is a slog. It's very dry. You have to care deeply about what he writes about or it will bore the fuck out of you. That said, it's likely to be important to economics the way Nate Silver is important to political polling. Like Silver, Piketty is kind of the first economist to go "you know, we have data. We could look at it rather than guessing." The conclusions he draws are not surprising, but they do put the lie to a lot of ideologically-driven political theory. 2) Economics is a closed system. Theoretically speaking, the amount of money all countries owe should exactly equal the amount of money all countries are owed. After all, neither a borrower nor a lender Mars be, right? however, when you add up current account surpluses for the planet and subtract current account deficits for the planet, you get a discrepancy of about 11%. That's money that goes from "on book" to "off book" as perspective shifts from "loan" to "debt." The only place it can go is offshore.