FILE - Russian President Vladimir Putin, right, and North Korea's leader Kim Jong Un shake hands during their meeting in Vladivostok, Russia, on April 25, 2019. North Korean leader Kim Jong Un’s possible trip to Russia might be like his first one in 2019, a rattling, 20-hour ride aboard a green-and-yellow armored train that is a quirky symbol of his family’s dynastic leadership. (Yuri Kadobnov/Pool Photo via AP, File)