People have to work harder, or make do with less, whichever side of income is taxed. The major difference between a sales tax and an income tax is the implementation. So, the federal government would much rather rely on wage taxation. Since government is inherently less efficient than the private sector, the more money it takes, the higher the rate of unemployment, even as it attempts to provide more services. But like the frog who was slowly boiled, the people have come to accept higher and higher levels of total taxation.
Reform movements come and go with the personalities and personal fortunes of the reformers.
An Investor's Business Daily guest columnist recently argued that it makes no difference where the government enters the income stream to divert public revenue. And there is some truth in that, assuming that government takes about the same amount of income in either case. And it assumes that there is no other practical way to support a government. Let us first explore the side-effects of an income tax, and then propose an entirely different means to raise public revenue. The size of the underground economy would become directly proportionate to the high tax rate on labor, as it has done in every western nation that has experimented with high tax rates.