Historian Amy Greenberg on The Mexican-American War: America's Forgotten Conflict | Road to 250

In this episode of Diplomatic Immunity, our host Kelly McFarland sits down with Dr. Amy Greenberg, professor at Penn State and author of A Wicked War: Polk, Clay, Lincoln, and the 1846 U.S. Invasion of Mexico, to explore one of the most consequential — and least remembered — wars in American history. We trace the origins of the Mexican-American War from the Texas Revolution and the annexation debate, through James K. Polk's deliberate provocation of conflict, to the rogue diplomacy of Nicholas Trist, whose defiance of presidential orders ultimately shaped the modern American Southwest. Topics covered: How US settlers in northern Mexico set the stage for Texas independence Why Texas remained unannexed for nearly a decade James K. Polk: the first "dark horse" president and the architect of Manifest Destiny The deliberate start of war — and Polk's lies to Congress Abraham Lincoln's spot resolutions and the rising anti-war movement The forgotten figure John Hardin and his connection to Lincoln's rise The US occupation of Mexico City and the "All of Mexico" movement Nicholas Trist's defiant negotiation of the Treaty of Guadalupe Hidalgo Why there is no monument in Washington, DC to this war — and why America forgot it 📚 A Wicked War: Polk, Clay, Lincoln and the 1846 U. S. Invasion of Mexico: https://www.amazon.com/Wicked-War-Lin... Produced by Freddie Mallinson and Mislav Majcan. Recorded on 7 May, 2026. Diplomatic Immunity, a podcast from the Institute for the Study of Diplomacy at Georgetown University, brings you frank and candid conversations with experts on the issues facing diplomats and national security decision-makers around the world. Funding support from the Carnegie Corporation of New York. Follow and Support our work:  https://isd.georgetown.edu/ https://www.instagram.com/gudiplomacy/ https://www.linkedin.com/company/institute-for-the-study-of-diplomacy/ https://twitter.com/GUDiplomacy 🔔 Subscribe for more in-depth conversations on diplomacy, foreign policy, and international relations. #ForeignPolicy #Diplomacy #History