Climate change is a national security issue, experts warn

Climate change is considered a threat multiplier by national security experts, many of whom are urging voters to keep this issue in mind when they cast their ballots. Drought, fires and major disasters all have the potential to spark mass migrations globally. "There's nothing that will deter (people) from fleeing to safety," former Homeland Security Secretary Michael Chertoff tells CBS News meteorologist and climate specialist Jeff Berardelli.