Retired U.S. Marine, former DHS official on Capitol security: "These are domestic enemies and we need to steel ourselves"

Officials in Washington D.C. are taking unprecedented security measures ahead of Inauguration Day as intelligence agencies monitor threats from domestic extremists. Retired United States Marine Colonel and former Department of Homeland Security press secretary David Lapan joins CBSN's Lana Zak with his assessment of the security threats facing the nation.