Reflections on Monetary Policy in the Open Economy

Aperennial topic of discussion among scholars and policymakers is how best to think about a benchmark for macroeconomics as it applies to monetary policy. Should the benchmark for policy analysis be the open economy with international interest rate linkages and flexible exchange rates (after all, major economies are in fact open with flexible exchange rates), or should it be the closed economy in which such linkages and exchange rate adjustments are assumed away? Of course, few if any policy makers would seek to guide policy by ignoring capital flows and exchange rates, but in many cases it appears as though the starting point for analysis is the closed‐economy macro model, these days a variant of the dynamic new Keynesian model. Those who start from a closed‐economy framework often have questions about how “openness” influences the analysis. How does the neutral real interest depend on “global” developments? Is the Phillips curve trade‐off between inflation and domestic output better or worse in the open versus the closed economy? Is “potential GDP” a function of global developments, or only of domestic resources available and domestic productivity? Perhaps most important, how—if at all—does openness influence the optimalmonetary policy rule? Is a Taylor rule the rightmonetary policy for an open economy? In 2002 Jordi Gali, Mark Gertler, and I published a paper in the Journal of Monetary Economics that developed a benchmark (at least in ourway of thinking) dynamic two‐country optimizing macro model of optimal monetary policies in the open economy. Our focus in that paper was deriving optimal policy rules in the two‐country model and assessing the gains from international monetary policy cooperation. In that paper, we emphasized the following implications of the model: