U.S. President Barack Obama, left, shakes hands with unidentified officials as he steps off the plane for a NATO summit in Lisbon on Friday, Nov. 19, 2010. U.S. President Barack Obama and the leaders of NATO's 27 other member nations will open a two-day summit Friday aimed at finding ways to keep the Cold War alliance relevant in the 21st century with revamped roles including ballistic missile defense, anti-piracy patrols, and counterterrorism. (AP Photo/Andre Kosters, Pool)