American tourists, like these visitors taking a guided tour in May, still have to provide one of 12 authorized reasons — such as visiting family or engaging in humanitarian work — for travel to Cuba. Desmond Boylan/AP hide caption

itoggle caption Desmond Boylan/AP

Secretary of State John Kerry spoke with NPR's Steve Inskeep at the State Department. Kerry said if Congress or a future president reverses a nuclear control agreement with Iran, U.S. credibility will suffer. Kainaz Amaria/NPR hide caption

itoggle caption Kainaz Amaria/NPR

Federal agents seized Elián González, held in a closet by Donato Dalrymple, in Miami in April 2000. Dalrymple rescued the boy from the ocean after his mother drowned when they tried to escape Cuba. Alan Diaz/AP hide caption

itoggle caption Alan Diaz/AP

Miami swimwear entrepreneur Mel Valenzuela (right) explains online strategies to Cuban business owners Victor Rodriguez (middle) and Caridad Limonta (left) in Wynwood this month. Miami boutique owner Monica Minagorri (rear) watches. Tim Padgett/WLRN hide caption

itoggle caption Tim Padgett/WLRN

Elian Gonzalez attends the closing ceremony of the legislative session at the National Assembly in Havana on Dec. 20, 2014. Gonzalez tells ABC News that he would like to visit the U.S. as a tourist. Ramon Espinosa/AP hide caption

itoggle caption Ramon Espinosa/AP

The Minnesota Orchestra under the direction of conductor Osmo Vanska (center) performs during a concert at the Cuban National Theater in Havana on Friday. Yamil Lage/AFP/Getty Images hide caption

itoggle caption Yamil Lage/AFP/Getty Images

President Obama meets Cuban President Raul Castro at the Summit of the Americas in Panama City on April 11. The White House says it wants to remove Cuba from its list of state sponsors of terrorism. Pablo Martinez Monsivais/AP hide caption

itoggle caption Pablo Martinez Monsivais/AP

President Obama with Cuban President Raul Castro during their historic meeting at the Summit of the Americas in Panama City. The Obama administration announced Tuesday it will remove Cuba from its list of state sponsors of terrorism. Pablo Martinez Monsivais/AP hide caption

itoggle caption Pablo Martinez Monsivais/AP

Senate Foreign Relations Committee member Sen. Marco Rubio, R-Fla., questions Secretary of State John Kerry on Capitol Hill last month. In an interview with NPR, Rubio reiterated his opposition to President Obama's dealings with Iran and Cuba. Pablo Martinez Monsivais/AP hide caption

itoggle caption Pablo Martinez Monsivais/AP

President Obama, seen shaking hands with Raul Castro at the Summit of the Americas in Panama, engaged in the first substantive face-to-face U.S.-Cuba talks in more than 50 years. Scott Horsley/NPR hide caption

itoggle caption Scott Horsley/NPR

Cuban President Raul Castro and President Obama shake hands as they meet on the sidelines of the Summit of the Americas in Panama City, Panama, on Saturday. It was the first substantive talk between leaders of the two countries in more than five decades. Pool/Scott Horsley hide caption

itoggle caption Pool/Scott Horsley