When monetary policy becomes impotent. Cutting the rate of interest is supposed to be the escape route from economic recession: boosting the money supply, increasing demand and thus reducing unemployment. But Keynes argued that sometimes cutting the rate of interest, even to zero, would not help. People, banks and firms could become so risk averse that they preferred the liquidity of cash to offering credit or using the credit that is on offer. In such circumstances, the economy would be trapped in recession, despite the best efforts of monetary policymakers. Keynesians reckon that in the 1930s the economies of both the United States and the UK were caught in a liquidity trap. In the late 1990s, the Japanese economy suffered a similar fate. But monetarism has no place for liquidity traps. Monetarists pin the blame for the Great depression and Japan’s more recent troubles on other factors and reckon that ways could have been found to make monetary policy work.