The last time President Barack Obama and Cuban President Raul Castro met face-to-face was in December 2013 — for a three-second handshake during Nelson Mandela's memorial service.
The two now could now cross paths again at the two-day Summit of the Americas in Panama, an encounter rife with opportunity and symbolism given the thaw in U.S.-Cuba relations announced at the end of last year.
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The U.S. for decades had blocked Cuba from attending the meeting, and Friday's start to the two-day summit marks the first time a Cuban leader will be present.
"That hopefully marks the beginning of the end of the Cold War in the Caribbean, in some ways the last vestiges of an era — a bygone era," said Cuba expert Peter Kornbluh, who is attending the summit and co-authored the book, "Back Channel to Cuba." "This summit will go down in history as a turning point in U.S.-Cuban relations and U.S. relations for the region."
Obama set a positive tone ahead of the summit, saying Thursday that a decision is near on whether to remove Cuba from the U.S.'s list of terrorism-sponsored countries.
A formal meeting between Obama and Castro at the annual gathering of Western Hemisphere nations would be the highest level of interaction between the U.S. and Cuba in more than half a century. While it was unclear if Obama and Castro will schedule a formal meeting, the two are widely expected to share at least a handshake.
Kornbluh said the presidents could potentially announce the complete restoration of normal diplomatic relations — or at least signal when exactly that could happen. Cubans have been waiting for financial sanctions and other trade restrictions to be lifted.
"President Obama has been up against pretty substantive opposition to rewriting a new chapter in Cuba policy. He needs to consolidate the decisions that he has made to move forward to repudiate the past and pursue a future of engagement," Kornbluh said. "That's why you would assume he'll use the summit to maximum benefit."
A normalized relationship between the U.S. and Cuba would mean shedding the decades of isolation and a trade embargo imposed during the regime of Fidel Castro, the older brother of Raul Castro.