Paul Krugman: Other People’s Dollars, and Their Place in Global Economics

Sydney, Australia — Soon after arriving here, I stopped at an A.T.M.; I needed some dollars, and all I had were dollars.

O.K., weak joke. What I needed were Australian dollars — Aussies — not U.S. greenbacks. There are actually four English-speaking countries with dollars of their own; the others are the Canadian loonie and the New Zealand kiwi. And you can learn a lot about the global economy, busting some popular monetary myths, by comparing those currencies and how they serve their economies.