U.S. President Barack Obama (C) greets the crowd as he arrives for a Franco-American alliance ceremony in Cannes November 4, 2011 at the end of the G20 Summit for Heads of State and Government. Obama and France's President Sarkozy took part in a ceremony celebrating the friendship between the U.S. and French armies. REUTERS/Markus Schreiber/Pool (FRANCE - Tags: POLITICS MILITARY)