Transcript for Kim Jong Un, Trump meet in person for the first time

and hail. The hostage standoff. The gunman barricaded with four children inside home. The officer shot. And the mystery cabin explosion. The family of five killed while on vacation. Good evening tonight from ngapore where we witnessed a whirlwind 24 hours. All eyes here and tonight around the world on what happens happening next. Just a short time we'll witness a truly historic moment. President trump meeting face-to-face with one of the world's most brutal dictators, Kim Jong-un. The president said he'll know in the fir minute if Kim Jong-un is serious. In stark contrast to the dictator who tested more bombs and missiles than his father and grandfather taking a selfie. A sight seeing walk surrounded by body guards. It was not a while Kim celebrating his missile blasts. Is he truly ready to give all that up. Jonathan Karl leading us off. Reporter: This is Donald Trump's moment. Even for this showman president, no move S been bolder, riskier. No spotlight more bright, more intense. At lunch with Singapore's prime minister, he sounded confident, but restrained. I think things could work out very nicely. Reporter: "Great to be in Singapore," he tweeted. "Excitement in the air!" At a meeting with the American diplomats at the embassy here, a pep talk. You are spectacular people. Thank you very much. Eporter: Even more, this is Kim Jong-un's moment. Will this 36year-old dictator make an historic turn? He spent the eve of the talks sightseeing. Even this night on the town for the world's most isolated leader of the world's most isolated nationwithout precedent. Srrounded by a phalanx of bodyguards, the same well-dressed security force earlier seen jogging alongside his car. Not since taking power seven years ago has he ventured so far from home. He visited Singapore's garby the bay, smiled as the foreign minister snapped a selfie. His next stop, a casino resort waving at stunned tourists as he made his way. The government of Singapore is picking up his hotel tab. Kim telling the prime minister, "If the summit pves successful, the name of Singapore will go down in history." President trump said he would know instantly if Kim is serious about making a deal. I think within the first Nute I'll know. How? Just my touch, eel. That's what I do I think I'll know quickly whether or not something positive will happen. Reporter: The two men spent most of last year trading inlts, an ominous words of war. Rocket man is on suicide mission for himself and for his regime. Reporter: Kim Jong-un posing more and more of a dire threat testing missiles capable of hitting the U.S., and a hydrogen mb some 10 times more powerful than the bomb dropped on Hiroshima. What will happen? Diplomats have been working day and night on a joint statement. In reality the answerepends on two men who relish their own unpredictability. There are only two people that can make decisions of this magnitude, and those two are going to be sitting in a room together. Jon Karl with us tonight in Singapore. Jon we know there will be two M meetings. Kim Jong-un and president trump face-to-face no advisers in the room, just their interpreters. The two men going face-to-face. It really comes down to them. The president himself has been tweeting this morning tweeted a short while ago TRE have been lots of other meetings with staff and representatives. The president said they have been going well. He said in the end that does. -- Doesn't matter. It will come down to those two leaders. Minutes ago he tweeted lashing out at the haters and losers who doubted him on all this suggesting he'll prove them wrong. Before the summit even happens Jon Karl leading us off. In the meantime many say one of the victories of Kim Jong-un is simply standing on the same stage as the preside of the United States. He'll get that chance after taking over in his mid twenties

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