Transcript for North and South Korea set to sit down for talks in 2 days

illegally as children, their fate hangs in the balance. Another subject. The standoff with North Korea. The president tweeted he has a bigger nuclear button. Now he's open to talks. Reporter: Ma that Raddatz is in South Korea with the latest. Good morning. Reporter: Good morning, Dan and Paula. We're just miles from the north Korean border. You can see those military-type bunkers behind me. The talks will take place along that border. Just days from now. ??? with just two days left until north and South Korea sit down to discuss the knot's participation in the olympic games, president trump giving his blessing. If something can happen and something can come out of those talks, that would be a great thing for all of humanity. Reporter: A meeting, president tump, from camp David, says is a result of his tough talk. If I weren't involved, they wouldn't be talking about olympics right now. He knows I'm not messing around. Reporter: Despite trump's threats, taunlts, and show of force, Kim Jong-un is close to per feblgting a nuclear-tipped missile that could potentially hit the U.S. Trump has said no talks with American negotiators unless the north agrees to end its nuclear program. He now says, he's willing to talk to Kim. I always believe in talking. Reporter: And there was no one we talked to in South Korea who didn't support talks. The fear of war here is constant. The artillery is easily seen from the side of the road. All guns pointing north. The barbed wire. The shelters. The barriers dezind crash on to the road way if north Korean soldiers storm south. But for the moment, says this farmer, there is hope Tuesday's dialogue will lead to more. Translator: Hopefully, if the international politics gets better, we want to live in peace. Reporter: Despite optimism about the talks and what president trump is saying there remains concern about what happens next. Dan and Paula? We want to bring in chief hanker. George Stephanopoulos. Let's pick up there with north Korea. Good morning the you, George. The president told reporters he's open to having talks with Kim Jong-un. They would come with conditions. He knows Kim Jong-un should know that he is not messing around. He didn't spell out thing conditions. It does seem to be some what of a turnaround. They have retired North Korea to say they will give up their nuclear program before. We seem to be in a new faze. South Korea wants to reduce tensions before the winter olympics next month. A significant decision to put off south korean-u.s. Military exercises until after the olympics. There does appear to be some kind of reduction in tensions as we head into talks between south Korea and North Korea. Except on the president's Twitter feed. We saw something extraordinary yesterday. The president of the united States feeling compelled to defend his own sanity. In front of reporters and if front of the nation. This has now become a partisan issue with some Democrats in congress introducing legislation for a mental fitness test for the president. At the end of the day, is anybody's mind going to change? You have had several psychiatrists question whether or not the president is fit as well. There's been a long-standing rule or precedent against having psychiatrists diagnose. Is there the Goldwater rule. The Goldwater rule. The president saying he's a very stable genius. You have the Michael Wolff book, that has sooefrl people from the president's inner circle, including his own son-in-law, questioning if he has the capacity to handle the job. That question is front and center right now. It's been revealed by this. I don't think it will go away. It's not been only partisan, either. You have Bob corker, the Republican senator from Tennessee who questioned his capacity in the past. Senator Lindsey graham. Republican. Now an ally of the president called him a kook. Lots of questions raised and the president's own inner circle. It's not like we're on the verge of the cabinet invoking the 25th amendment. Not anywhere close. The price tag of the wall is reportedly going to be $18 billion. The president says he's not going to extend DACA unless Democrats agree to the wall. Somewhat the likelihood any of this gets done? And the clock is ticking. The government shutdown is approaching on January 19th. The Democrats say they want DACA included in any bill to keep open the government. Is a compromise possible with some kind of border security beef-up that the president can call a wall and the Democrats will say is not a wall? I don't know the answer to that question right now. Thing that's what is at the heart of these negotiations. It's art of the deal time. George has a big show coming up. He'll go one on one with U.S. Ambassador to the U.N. Nikki Haley. And senators Sanders and ton. Plus the powerhouse "Roundtable" breaks down the fallout over the blockbuster book on the president and the white house. Thank you, George. Let's send things to Ron Claiborne with a look at the

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