Next week, Ukraine will mark a violent anniversary: four years since Russia’s full-scale invasion. The war has already reshaped Europe’s security order, strained Western unity, and tested the limits of diplomacy. It’s a conflict that historian Serhii Plokhy explores in his new book "David and Goliath: Commentaries on the Russo-Ukrainian War." He joins the show to discuss. 

Also on today's show: actors Billy Crudup and Denise Gough; author Emily Galvin