Transcript for Kim Jong Un issues a threat to America in his New Year's message

Back here at home, and president trump returning to Washington tonight after his Florida holiday, facing a fresh threat from Kim Jong-un. The north Korean lead er the president calls little rocket man, touting his arsenal, and warning the button is on his desk. ABC's David Wright is in west palm beach. Reporter: Tonight, as president trump heads back to the white house, the new year brings plenty of big challenges. He acknowledged last much last night at mar-a-lago, obtained by CNN. We have some pretty good enemies out there, but step by step, they're being defeated. They're some bad people. Bad people. But that's okay. Some day, maybe they'll love us. Reporter: Hard to imagine the young leader trump has belittled as little rocket man would ever come around. North crekorea's Kim Jong-un. His new year's message included a threat. "The U.S. Should know that the nuclear button is on my December," he said. "The entire U.S. Mainland is within our nuclear strike range." That may or may not be true. President trump was asked about that. We'll see. We'll see. Reporter: If the recent past is any guide, trump won't take kindly to any overt threats. They will be met with fire and fury like the world has never seen. Reporter: The former chairman of the joint chiefs of staff offered this grim assessment to Martha Raddatz this weekend. We're actually closer, in my view, to a nuclear war with North Korea and in that region, than we've ever been, and I just don't see how -- I don't see the opportunities to solve this diplomatically at this particular point. Reporter: The U.S. Has long considered North Korea's nuclear ambitions to be a threat to national security, and Kim Jong-un now insists that his country's nuclear readiness is a reality. A huge test for president trump. Tom? David Wright for us. David, thank you.

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