What is the power to tax and spend and explain how it has been used overtime to expand the federal power?

Initially Congress was granted the power to collect taxes. The collection of income taxes however, was to have been a temporary measure, and the bulk was to have been paid by the wealthy. However, at this point there are numerous taxes, and the collection of them is not ending. In addition, the wealthy pay very few taxes, and the bulk of paying for the government falls on the shoulders of the middle class.