We like to think of America as a class-free society where anyone who works hard can achieve economic success. Historian Nancy Isenberg says it’s a promise as old as our nation, and that it’s always been a myth. She argues that landowners and the elite have only valued the poor for their labor - while describing them as vagrants, crackers, squatters, and rednecks. Isenberg joins us Tuesday to trace what she calls the 400-year untold history of class in America. Her book is called White Trash.