President Barack Obama has said the United States is considering putting North Korea back on its list of terrorism sponsors after the hacking of Sony Pictures. Last week, the studio canceled the release of the screwball comedy film "The Interview," about a plot to kill North Korean leader Kim Jong-un, following threats against theaters and a hack of corporate data, which officials say was ordered by the North Korean government. North Korea was on the U.S. list of state terrorism sponsors for two decades until the White House removed it in 2008, after Pyongyang agreed to full verification of its nuclear sites. Last month's cyber-attack was claimed by a group calling itself The Guardians of Peace. The group released the salary and Social Security numbers of thousands of Sony employees, including celebrities, and also threatened to attack screenings of the film. Although U.S. officials have said North Korea is behind the attack, many experts have questioned whether the evidence is sufficient. North Korea has denied involvement and proposed a joint investigation with the U.S. government to prove it. We are joined by two guests: Tim Shorrock, an investigative journalist who has been writing about U.S.-Korea relations for 30 years; and Christine Hong, assistant professor at University of California, Santa Cruz, and an executive board member of the Korea Policy Institute. Hong has spent time in North Korea, including a visit to the country as part of a North American peace delegation.