PRAGUE, CZECH REPUBLIC - SEPTEMBER 09: U.S. soldiers from the 2nd Cavalry Regiment of the US Army smile before arrival of NATO Secretary General Jens Stoltenberg at the Czech army barracks on September 9, 2015 in Prague, Czech Republic. U.S. soldiers are traveling in the 'Danube Ride' convoy from their home base in Vilseck, Bavaria, Germany to Hungary where they will participate in the NATO Brave Warrior 2015 exercise. NATO Secretary General Jens Stoltenberg is in the Czech Republic for a two-day official visit. (Photo by Matej Divizna/Getty Images)
