In the days since Vladimir Putin ordered Russian forces to invade Ukraine, its citizens have taken up arms to defend their borders and their right to self-determination. Where is the rest of the world in all of this?

To help understand the current situation and how we got here, Jane Coaston talks with Alexander Vindman, a retired Army lieutenant colonel who was the director for European and Russian affairs at the National Security Council from 2018 to 2020. Vindman was also a key witness at Donald Trump’s first impeachment trial, having listened in on the notorious 2019 call in which Trump asked President Volodymyr Zelensky of Ukraine to investigate Joe Biden. Vindman says of the Western response to the invasion, “We need to drop these incremental approaches that are intended for a kind of peacetime environment,” because “we’re in a new Cold War.”

What is your take on Russia’s invasion of Ukraine? We want to hear from you. Share your thoughts in the comments on The New York Times website once you’ve listened to the debate.

Mentioned in this episode:

• Alexander Vindman’s book, “Here, Right Matters: An American Story”
• “America Could Have Done So Much More to Protect Ukraine,” by Alexander Vindman in The Atlantic
• “Not One Inch: America, Russia, And the Making of Post-Cold War Stalemate,” by M.E. Sarotte
• An interview with the historian Serhii Plokhy in The New Yorker: “Vladimir Putin’s Revisionist History of Russia and Ukraine”
• People to follow on Twitter, as suggested by Alexander Vindman: Igor Girkin, Michael Kofman, Rob Lee, Michael McFaul
• The Hebrew Immigrant Aid Society’s Ukraine crisis response fund
• The MOAS humanitarian relief effort for Ukraine

(A full transcript of the episode will be available midday on the Times website.)