It would be nice to dismiss the stupid things that Americans believe as harmless, writes Timothy Egan, but a culture of misinformation can have very serious consequences. "False belief in weapons of mass-destruction led the United States to a trillion-dollar war. And trust in rising home value as a truism as reliable as a sunrise was a major contributor to the catastrophic collapse of the economy. At its worst extreme, a culture of misinformation can produce something like Iran, which is run by a Holocaust denier." Egan homes in on Rush Limbaugh and Fox News in examing media sources of misinformation.