NATO leaders gather Tuesday for what could be a historic summit, or one marred by divisions

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AP1949

FILE - Belgium's Prime Minister Paul-Henri Spaak, seated center, signs the North Atlantic Pact in Washington, DC, April 4, 1949, flanked by Belgium's Ambassador to the U.S., Baron Silvercruys, left, and John W. Foley of the U.S. State Department. Seated behind, from left, are Britain's Ernest Bevin, Norway's Halvard Lange, Luxembourg's Joseph Bech, Iceland's Bjarni Benediktsson, Denmark's Gustav Rasmussen, U.S. President Harry S. Truman, U.S. Secretary of State Dean Acheson; Canada's Lester Pearson, France's Robert Schuman, Italy's Count Carlo Spforza, Holland's Dirk Stikker and Portugal's Jose Caeiro Da Matta. (AP Photo, File)