U.S. President Donald Trump speaks during a national security strategy speech at the Ronald Reagan Building in Washington, D.C., U.S., on Monday, Dec. 18, 2017. The national security strategy, a document mandated by Congress, will describe the Trump administration's approach to a range of global challenges including North Korea's nuclear program, international terrorism, Russian aggression and China's rising influence. Photographer: Jim Lo Scalzo/Pool via Bloomberg
