U.S. Secretary of State Hillary Clinton, center right, poses with students from the east German city of Oranienburg, next to one of 1,000 large plastic-foam dominoes, prior to commemorations of the 20th anniversary of the fall of the Berlin Wall, in Berlin, Germany, Monday, Nov. 9, 2009. East Germany's fortified border crumbled on the evening of Nov. 9, 1989, after 28 years holding in the country's citizens, a pivotal moment in the collapse of communism in Europe that followed a confused announcement by a senior official. The Brandenburg Gate is seen in the background.