Vintage American history photo of a nuclear weapon test by the American military at Bikini Atoll, Micronesia on July 25, 1946. The explosion was part of Operation Crossroads. John Parrot/Stocktrek Images/Getty Images hide caption

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Donald Trump spoke at the American Israel Public Affairs Committee Conference in March when he was a candidate for the GOP presidential nomination. Saul Loeb /AFP/Getty Images hide caption

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Saul Loeb /AFP/Getty Images

This undated photo released by North Korea's official Korean Central News Agency on Nov. 11 shows North Korean leader Kim Jong-Un at a defense detachment on Mahap Islet. KNS/AFP/Getty Images hide caption

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KNS/AFP/Getty Images

How Uncertainty In The Korean Peninsula Could Be A 'Recipe for Disaster'

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A picture taken on April 20, 2010, shows a Russian nuclear-capable Iskander ballistic missile launcher during a military parade rehearsal outside Moscow. Russia transferred Iskander-M missile launchers within range of three Baltic states earlier this month. Alexander Nemenov/AFP/Getty Images hide caption

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Alexander Nemenov/AFP/Getty Images

'A Dangerous Situation' As U.S.-Russia Tensions Spill Over To Nuclear Pacts

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Visitors look at the China-North Korea Friendship Bridge across the Yalu River from Dandong, in northeast China. A company operating from Dandong is under fresh sanctions by the U.S. Greg Baker/AFP/Getty Images hide caption

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Greg Baker/AFP/Getty Images

U.S. Targets Chinese Company For Supporting N. Korean Nuclear Program

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A tourist at the Bradbury Science Museum in Los Alamos, New Mexico, in February examines a full-size replica of the "Fat Man" atomic bomb which was dropped on Nagasaki, Japan, on Aug. 9, 1945. Los Alamos is home to the Los Alamos National Laboratory which was established in 1943 as part of the Manhattan Project. Robert Alexander/Getty Images hide caption

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Members of the 320th Missile Squadron missile combat crew work through a scenario in the 90th Operations Support Squadron's Missile Procedure Trainer on F.E. Warren Air Force Base, Wyo., in June 2014. The MPT is a simulator that allows missile crews to practice contingencies they might face while on alert. R.J. Oriez/U.S. Air Force hide caption

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R.J. Oriez/U.S. Air Force

President Obama, speaking in Prague in 2009, said: "I state clearly and with conviction America's commitment to seek the peace and security of a world without nuclear weapons." While Obama has pushed for a reduction in nuclear arms throughout his presidency, he has also agreed to an expensive upgrade of America's aging nuclear arsenal. Charles Dharapak/AP hide caption

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Charles Dharapak/AP

A North Korean man reads a local newspaper on Sunday with an image of leader Kim Jong Un. Kim said during a critical ruling party congress that his country will not use its nuclear weapons first unless its sovereignty is invaded, state media reported. Kim Kwan Hyon/AP hide caption

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Kim Kwan Hyon/AP

N. Korea Wants Economic And Nuclear Expansion, But One Undercuts The Other

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North Korean leader Kim Jong-Un reporting works of North Korean Workers Party Central Committee during the second-day of the 7th Workers Party Congress in Pyongyang. KCNA/AFP/Getty Images hide caption

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KCNA/AFP/Getty Images

A ballistic surface-to-surface missile is fired by Iran's Revolutionary Guard, during a maneuver, in an undisclosed location in Iran on Wednesday. Omid Vahabzadeh/AP via Fars News Agency hide caption

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Omid Vahabzadeh/AP via Fars News Agency

People watch a news report at a railway station in Seoul on Feb. 3. North Korea launched a long-range rocket Sunday local time, defying international criticism. Jung Yeon-Je/AFP/Getty Images hide caption

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Jung Yeon-Je/AFP/Getty Images