File - United States President Bill Clinton, center right, poses for a group photo with former US Presidents Jimmy Carter, left, George H.W. Bush, center left, and Gerald R. Ford, right, at the White House in Washington, DC on September 13, 1993. The leaders gathered at the White House for the Middle Eastern Treaty Signing, also known as Oslo 1, and for the North American Free Trade Agreement, also known as NAFTA, kick-off the following day. Photo by White House via CNP/ABACAPRESS.COM