"In practice, all that “the exchange rate is the purview of the Treasury” means is that no official other the Treasury secretary is supposed to talk about it (and even he isn’t supposed to say very much). That strikes me as a shame. Perhaps if government officials could talk about the exchange rate forthrightly, there would be more understanding of the issues and more rational policy discussions.

Such discussions would start with some basic economics. The desire to trade with other countries or invest in them is what gives rise to the market for foreign exchange. You need euros to travel in Spain or to buy a German government bond, so you need a way to exchange currencies."

"We aren't enchanted by Bayesian methods merely because they're beautiful. The beauty is a side effect."