Dele said:
Keynesians lack faith on the good old free market.
Our markets are not perfectly free. They will never be perfectly free. Invoking the 'free market' as an excuse to avoid explaining your position is not a terribly convincing argument. In
general terms, increased economic freedom typically increases efficiency. However, economic efficiency is not the cardinal goal of modern societies (and god forbid that becomes the case). Efficiency has virtually no bearing on measures of quality of life and says nothing about the work-leisure tradeoff. Income equality? Irrelevant. Education becomes valuable only for its role in human capital formation.
Furthermore, the very idea of government of any form is antithetical to a perfectly free market. As soon as one cent of tax is levied and spent, markets become 'distorted.' Even before the rise of the welfare state, activities such as maintaining an army created entire industries and stimulated incredible volumes of international trade (one need look only to Europe before the Great War to see the extent to which obsession over mobilization schedules and cutting-edge weaponry impacted its markets). In the modern era this is even more pronounced (the term 'military-industrial complex' springs immediately to mind.)
Other enormous government expenditures (social security, medicare/aid, etc.) influence markets as well. This is not a bad thing. It's worth a small decrease in efficiency to know that our elderly will be supported, that the sick can receive care, that children will be educated. In the face of a massive (in historical terms, though rather small when compared with other developed nations) government, blaming monetary policy for 'increasing the volatility of the free market' is ludicrous.
The Federal Reserve is also the mechanism through which debts are brokered. The prerogative to manipulate interest rates and the money supply is essential to maneuvering the United States in the international trade and financial systems, neither of which is a market best described by the term 'free.' In addition to questions of valuation vis-a-vis other currencies, pursuing an obsessive stable price policy also leaves a currency open to speculation attacks. Look at the experience of eurozone countries in the 1990s as they tried to peg their currencies to one another in the 'snake' system. Britain's financial markets were devastated by a speculatory attack, causing it to drop from the monetary union entirely, and galvanizing anti-Union sentiment there.
The fed tries to strike a balance between growth and inflation, guiding the economy towards full-employment output and attempting to deflate bubbles, controlling inflation (example: the engineered recessions of the 1980s and 90s) and stimulate growth when it lags (Example: business page of a newspaper). You've asserted repeatedly that these actions 'increase volatility,' but in the absence of a model to illustrate your assertion it's impossible for me, or anyone else not so immediately inclined, to sympathize with your point of view.