A Nebraska middle school’s concerns about the safety of its students led to one of the largest investigations into illegal child labor in this country. Scott Pelley reports. Bill Whitaker visits California’s massive lithium reserve to see why some are calling this the next phase of the Industrial Revolution. Photographer James Nachtwey has made a career covering the world’s most violent conflicts. He tells Anderson Cooper why documenting acts of compassion in the darkest times makes him believe in humanity.See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.