This paper examines the missing transmission mechanism in Friedman's and Schwartz's monetary explanation of the Great Depression. We review the challenge provided by the decline in nominal interest rates in the early 1930s, and show that the monetary explanation requires not just that there were expectations of deflation, but that they were caused by monetary contraction. Using a detailed analysis of Business Week magazine, we find evidence that monetary contraction and Federal Reserve policy contributed to expectations of deflation during the downturn. This suggests that monetary shocks may have depressed spending and output in part by raising real interest rates.

Monetary policy-makers' beliefs about how the economy functions are a key determinant of the conduct of policy. That monetary policy has little impact under the prevailing circumstances is a belief which has resurfaced periodically over the Federal Reserve's 100-year history. In both the 1930s and the 1970s a belief in the ineffectiveness of monetary policy led to policy inaction and poor economic outcomes. For some of the recent period, the same view appears to have limited the policy response to prolonged high unemployment in the presence of low inflation.