Money makes the world go around, faster and faster every day. On NPR's Planet Money, you'll meet high rollers, brainy economists and regular folks -- all trying to make sense of our rapidly changing global economy.
NPR: Planet Money Podcast navigateright Episode
The U.S. has a really conflicted history with the income tax. For most of American history, there was no income tax at all. At one point it was ruled unconstitutional.
Today, income tax is the federal government's main source of revenue. That raises a question: How did something that was once so strange to us become so central?
The answer includes a few wars, a Supreme Court justice on his deathbed, and Donald Duck.