Transcript for Trump puts focus on North Korea during Japan trip
The latest on president trump. On air force one heading back from a diplomatic mission to Tokyo where he became the first foreign leader to meet Japan's new emperor, defended Kim Jong-un and broke with tradition by echoing that dictator's attacks on former vice president Joe Biden. Jon Karl joins us now. This trip unusual in so many ways. Reporter: It was designed to bolster U.S. Relations with one of America's closest allies but the spotlight went to north Korea as he bucked his own national security adviser by defending Kim Jong-un's recent missile tests. For much of the trip marked by pomp and circumstance, president trump defied the longtime tradition of avoiding partisan politics on foreign soil. Siding with a brutal dictator over a former American vice president and senator. Kim Jong-un made a statement that Joe Biden is a low I.Q. Individual. He probably is based on his record. Reporter: President trump also created a stir by praising North Korea's Kim Jong-un, who the Japanese and much of the world consider a threat. At a joint press conference with Japanese prime minister shinzo Abe, the president called Kim a very smart man and he said he isn't concerned about the short-range ballistic missiles Kim launched earlier this month. You're not bothered at all by the small missiles. I am not. Reporter: On the world stage president trump contradicted his own national security adviser John Bolton who told a reporter on Saturday that the short-rank missile tests no doubt violate a U.N. Security council My people think it could have been a violation as you know. I view it differently. I view it as a man, perhaps he wants to get attention and perhaps not. Who knows? Reporter: Trump continued to flout the tradition of avoiding politics on foreign soil by criticizing Biden on Twitter throughout the trip, criticizing his record fro halfway around the world. As for Biden, George, he didn't say anything. He appeared to be avoiding making any response to the president, perhaps that will happen once the president returns here to the united States later today. Team wanted to wait until the president was on American soil. Meantime, Jon, the president trying to tamp down any tension with Iran, bringing back that war talk. Reporter: He made it absolutely clear saying explicitly that he is not interested in regime change in Iran and once again suggested that he is open to having talks with the leaders of Iran. Jon, how are you staying dry out there? A lot of weather in the show. We wanted to show you some from
This transcript has been automatically generated and may not be 100% accurate.