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Slow pace of Ukraine's counteroffensive prompts questions
12m 24s
U.S. Joint Chiefs chairman Gen. Mark Milley described Ukraine's effort to retake territory in the east and south as a tough and difficult fight. Forces have been slowed by minefields and intense Russian resistance. To learn more about the offensive and its prospects for success, William Brangham spoke with retired Army Col. Gary Espinas and Kimberly Kagan of the Institute for the Study of War.