President Barack Obama waves from the steps of Air Force One as he prepares to leave Mexico for Costa Rica at the Benito Juarez International airport in Mexico City, Friday, May 3, 2013. Obama is to meet with Costa Rican President Laura Chinchilla before joining leaders from the Central American Integration system. The regional network also includes the leaders of Belize, El Salvador, Guatemala, Honduras, Nicaragua and Panama. (AP Photo/Eduardo Verdugo)