North Korea saber rattles with threats of a 'preemptive nuclear attack' on U.S.

North Korea is threatening to launch a pre-emptive nuclear attack against the U.S. It's on the same day that the U.N. slapped the rogue nation with new sanctions targeting the country's nuclear program.

But international condemnation and punishment has done little to deter North Korea's dictator Kim Jong Un.

In 14 months of being in power, Kim has launched two long-range missiles.

Once last April, then again in December. Last month, the country with a million man army conducted a third nuclear test.

How dangerous is the 30-year-old Kim Jong Un? And could he be worse than his father?

OutFront tonight: Victor Cha, a nuclear weapons expert and the former director for Asian Affairs at the National Security Council under President Bush and Gordon Chang, author of "Nuclear Showdown: North Korea Takes on the World."