Gravitas: North Korea tests undersea nuclear armageddon | Will Kim start war with South Korea?

North Korea has tested another nuclear weapon system, an underwater attack drone called the "Haeil-5-23". It was tested in waters off the east coast to mark its protest against this week's joint military drills by South Korea, the U.S., and Japan. The weapons test comes after Kim Jong Un declared South Korea is number one enemy and threatened to go to war if he feels threatened.