Austrian economist, Murray Rothbard (1926–1995), in his 1971 article “Milton Friedman unraveled“:
One of Friedman’s most disastrous deeds was the important role he proudly played, during World War II in the Treasury Department, in foisting upon the suffering American public the system of the withholding tax. Before World War II, when income tax rates were far lower than now, there was no withholding system; everyone paid his annual bill in one lump sum, on March 15. It is obvious that under this system, the Internal Revenue Service could never hope to extract the entire annual sum, at current confiscatory rates, from the mass of the working population. The whole ghastly system would have happily broken down long before this. Only the Friedmanite withholding tax has permitted the government to use every employer as an unpaid tax collector, extracting the tax quietly and silently from each paycheck. In many ways, we have Milton Friedman to thank for the present monster Leviathan State in America.