NATO leaders are analyzing how best to respond to Russia’s escalation in Ukraine after the consequences of Moscow’s aggression finally hit their territory. Two people are dead in Poland after what are believed to be parts of a Ukrainian air defense missile landed there last night. President Zelensky is calling for further investigations, while Warsaw, Washington and NATO believe the deadly incident happened as Ukraine blocked Russian cruise missiles from hitting western Ukraine. For a few hours of intense consultations and investigations, there was deep anxiety about whether a dangerous new frontier had been breached. To discuss, Christiane speaks with the prime minister of Estonia, a NATO member on Russia’s border. Also on today's show: Professor of Marketing Scott Galloway; actor Edward Norton; author Clint Smith.To learn more about how CNN protects listener privacy, visit cnn.com/privacy