Keynes did not challenge the efficacy of price adjustment mechanisms in clearing particular markets in the Marshallian partial equilibrium theory on … - James Tobin

Each sector is... constrained by its own net worth... The individual economic unit can neither change the legacy of the past nor... affect by... portfolio choices... market valuations of his assets.

Keynesian economics at a minimum provides a license for welfare state measures and other government efforts towards redistribution of wealth. The license is the faith that macroeconomic stabilization and prosperity are compatible with a wide range of social policies, that modern capitalism and democracy are robust enough to prosper and progress while being humane and equitable. That faith conflicts with the visions of extreme Right and Left, which agree that extremes of wealth and poverty, of security and insecurity, are indispensable to the functioning of capitalism. Keynesian policies helped to confound those dismal prophecies in the past; I think they will do so again.

The historic terrain of macro-economic theory is the explanation of the levels and fluctuations of overall economic activity. Macro-economists have been especially interested in the effects of alternative fiscal, financial, and monetary policies.