Former Soviet Union leader Mikhail Gorbachev, former Polish President Lech Walesa and former President of South Africa Frederik W. de Klerk, from right, participate in the 10th World Summit of Nobel Peace Laureates in Berlin, Germany, Tuesday, Nov. 10, 2009. Due to the 20th anniversary of the fall of the Berlin Wall, the two-day-summit takes place in the German capital.
(AP Photo/Franka Bruns)