This article is based on the presidential address presented to the Society for Historians of the Gilded Age and Progressive Era at the meeting of the Organization of American Historians in Los Angeles in 2023. Its focus is Maury Diggs and Drew Caminetti, two white men from Sacramento, California, charged with violating the Mann Act (known as the White Slave Trafficking Act) in 1913. The Gilded Age and Progressive Era obsession with white slavery, a phenomenon that has particular resonance in today’s climate, reveals the power of moral panics. Examining the steps, and missteps, that various legal, social, and political entities, including all three branches of government, took in response to Diggs and Caminetti’s actions highlights some of the major social changes gripping the nation. Moral panics can be investigated as crucial historical sites of contestation, revealing efforts to neutralize or turn back the societal changes perceived to be the greatest threat to the prevailing social power structure—in this case foreigners, the new leisure culture, the liberalization of sexual attitudes, and the threat of female independence. Understanding the origins and repercussions of past moral panics can help identify, understand, and possibly defuse future panics.