Walesa, de Klerk, Gorbachev and Carter participate in Panel Discussion at Peace Summit in Chicago

Former Polish President Lech Walesa (L-R), former South African President Frederik Willem de Klerk, former Soviet President Mikhail Gorbachev and former U.S. President Jimmy Carter participate in a panel discussion entitled "New Challenges for Peace" moderated by Chris Jansing (R) at the 12th World Summit of Nobel Peace Laureates on April 23, 2012 in Chicago. UPI/Brian Kersey