US President Barack Obama, in his maiden address to the United Nations, declared his commitment to moving forward with the ratification of the Comprehensive Test Ban Treaty that will prohibit nuclear testing. He also set a January goal for starting negotiations on a treaty to end production of fissile material weapons.
On June 30, Donald J. Trump became the first US president to set foot in North Korea. Trump made history when stepped across a low concrete marker accompanied by North Korean leader Kim Jong-un and walked a few steps into the North. The two leaders agreed to have their negotiators resume an effort to reach what has so far been an elusive nuclear deal. US President Donald J. Trump, accompanied by North Korean leader Kim Jong-un, stepped into North Korea at the border village of Panmunjom on June 30. Trump is the first sitting US president to set foot in North Korea. (Reuters/Kevin Lamarque)