This paper first investigates the effects of alternative modes of deficit financing on the unemployment rate, the inflation rate and the real interest rate, within the framework of a small complete macroeconomic model. Secondly, it examines the nature of monetary and fiscal reaction functions. The two periods 1923–1960 and 1961–1982 are considered, with substantial differences in behaviour and policy being shown to exist between them. The most important conclusion is that long‐run monetary neutrality properties shown to exist over the latter period are not intrinsic to the U.S. economy, but rather are the result of the stabilization policies being conducted over that period.