A tax, in the general understanding of the term, and as used in the Constitution, signifies an exaction for the support of the Government. The word has never been thought to connote the expropriation of money from one group for the benefit of another.
From the accepted doctrine that the United States is a government of delegated powers, it follows that those not expressly granted, or reasonably to be implied from such as are conferred, are reserved to the states, or to the people. To forestall any suggestion to the contrary, the Tenth Amendment was adopted.
The question is not what power the federal government ought to have, but what powers in fact have been given by the people.... The federal union is a government of delegated powers. It has only such as are expressly conferred upon it and such as are reasonably to be implied from those granted.