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US Secretary of State Rex Tillerson arrives to attend a meeting on Syria at the World Conference Center in Bonn, western Germany, February 17, 2017. / AFP / POOL / Oliver Berg (Photo credit should read OLIVER BERG/AFP/Getty Images)

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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)

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