Where does the us government get the power to impose tax today?

The U.S. government derives its power to impose taxes primarily from the Constitution, specifically Article I, Section 8, which grants Congress the authority to levy taxes to provide for the common defense and general welfare. Additionally, the 16th Amendment, ratified in 1913, explicitly allows Congress to levy an income tax without apportioning it among the states based on population. This constitutional foundation enables the federal government to collect various forms of taxes, including income, corporate, and excise taxes.