Things could get worse before they get better in Ukraine, says the U.S. Army's Christine Wormuth

Christine Wormuth, 25th Secretary of the U.S. Army and former director of the International Defense and Security Center at RAND Corporation, joins 'Squawk on the Street' to discuss how she assesses the situation on the ground in Ukraine, what U.S. military services are doing in Europe and modernization efforts she's seeing in the U.S. Army.