This is a country awash in monuments. They adorn traffic circles, street corners and, of course, Public Square. We've memorialized everything from famous soldiers and statesmen, to big ideas or major events - and a lot in between. Yet our ambivalence towards these monuments is as old as our enthusiasm for them. Case in point: The Washington Monument. Ever wonder why there isn't actually a image of Washington on it? The American History Guys look at the people and the thinking behind American icons. The Sound of Ideas returns on Tuesday.