North Korea Tensions
US President-elect Donald Trump exits elevators to talk with the media at Trump Tower on December 6, 2016 in New York. / AFP / Eduardo Munoz Alvarez (Photo credit should read EDUARDO MUNOZ ALVAREZ/AFP/Getty Images)
Now playing
01:44
Trump slams N. Korea, China in tweets
Now playing
01:27
North, South Korean leaders to meet again
Now playing
01:44
New images show N. Korea dismantling test site
Now playing
00:40
Pompeo dismisses N. Korea's 'gangster' comments
SINGAPORE - JUNE 12: In this handout photo, North Korean leader Kim Jong-un shakes hands with U.S. President Donald Trump during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore. U.S. President Trump and North Korean leader Kim Jong-un held the historic meeting between leaders of both countries on Tuesday morning in Singapore, carrying hopes to end decades of hostility and the threat of North Korea's nuclear program. (Photo by Kevin Lim/THE STRAITS TIMES/Handout/Getty Images)
Now playing
01:56
Kim Jong Un snubbed Mike Pompeo, source says
WASHINGTON, DC - MAY 09: National Security Adviser John Bolton speaks on a morning television show from the grounds of the White House, on May 9, 2018 in Washington, DC. Yesterday President Donald Trump announced that America was withdrawing from the Iran nuclear deal. (Photo by Mark Wilson/Getty Images)
Now playing
01:34
Bolton: US has plan for denuclearizing N. Korea