Fighting for a U.S. federal budget that prioritizes peace, economic security and shared prosperity
So, you've probably just finished settling up your 2015 income tax bill with the IRS. (Or at least you should have, what with the due date being today and all.)
But unlike with other bills -- say, for groceries, utilities and clothes -- you may not be sure exactly what you just paid for.
The answer is: A lot of things.