Russia's invasion of Ukraine raises several ethical questions: Why did diplomacy fail? What does the invasion mean for the principle of sovereignty? How does history inform the present and suggest the future? Are sanctions an appropriate and effective response, and what principles should guide their implementation?

Carnegie Council President Joel Rosenthal and Senior Fellow Nikolas Gvosdev discuss the ramifications of Putin's decision and the ethical principles at stake in the current crisis.

For more, please go to carnegiecouncil.org.