North Korea threatens to launch "Christmas gift" to the U.S.

U.S. intelligence officials say North Korea could launch a short-range missile test or rocket engine test at any time. They are also watching for a long-range test, which they say is possible, but not expected until after the start of the New Year. Gordon Chang, author of "Nuclear Showdown: North Korea takes on the world" joins CBSN to discuss the latest escalation.