Russia's invasion of Ukraine is one of the biggest and most confusing political events of our lifetimes. We aim to bring some clarity in this special four-part series from Vox Conversations and host Zack Beauchamp, The War in Ukraine, Explained. In part three, Zack speaks with professor, blogger, and nuclear arms expert Jeff Lewis about the looming nuclear threat of the conflict in Ukraine. They discuss the probability of escalation by both Russia and the U.S., what "tactical" nuclear weapons really are and how they're misunderstood, the double-edged sword of deterrence, and some of the ethical, political, and psychological realities of managing large stockpiles of devastating nuclear weapons. Host: Zack Beauchamp (@zackbeauchamp), Senior Correspondent, Vox Guest: Jeff Lewis (@ArmsControlWonk), founder and contributor, Arms Control Wonk; director, East Asia Nonproliferation Program, Middlebury Institute of International Studies at Monterey References:  "Is Russia committing genocide in Ukraine?" by Zack Beauchamp (Vox; Apr. 13) Enjoyed this episode? Rate Vox Conversations ⭐⭐⭐⭐⭐ and leave a review on Apple Podcasts. Subscribe for free. Be the first to hear the next episode of Vox Conversations by subscribing in your favorite podcast app. Support Vox Conversations by making a financial contribution to Vox! bit.ly/givepodcasts This episode was made by:  Producer: Erikk Geannikis Editor: Amy Drozdowska Engineer: Paul Robert Mounsey Deputy Editorial Director, Vox Talk: Amber Hall Learn more about your ad choices. Visit podcastchoices.com/adchoices