Why does the constitution allow the federal government to levy taxes?

The Constitution restricted the ablility of the Feds to tax and specifically forbids direct taxes like income tax, social security taxes and other payroll deductions. It was changed by Constitutional amendment. The promise was the payroll tax would never be more than 1% and would only apply to the very rich and would go away as soon as the cost of the Spanish American war was paid off.

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The basic thing is that without the taxations of all types of your dues it could not be operated any more. It is also fact that Section 8 of the Constitution does, and the 16th amendment specifically authorizes the income tax. Federal Tax Levy is involving all around taxes and taxation departments transactions. Before that, income tariffs were the main source of revenues for the federal government. So anybody who tells you tariffs failed doesn't know history before 1913 and he did not have any kind of idea about failed of tariffs or anything.

http://www.federaltaxresolution.com/tax-garnishment-wage-bank-levy.php