Historic Obama-Castro handshake in Panama?

President Obama and Cuban leader Raul Castro could exchange a glancing handshake or brief chat on Friday at the seventh annual Summit of the Americas in Panama, which Cuba is attending for the first time. It would be an historic albeit unofficial meeting between the two, and senior U.S. officials say they could also meet for a more in-depth discussion on Saturday, reports CBS News chief White House correspondent Major Garrett.

White House officials confirmed that Obama and Castro had spoken over the phone Wednesday before the president departed Washington.

It could be another big step in breaking down barriers between the U.S. and Cuba.

Taking Cuba off the list of state sponsors of terrorism is a power Mr. Obama possesses and intends to exercise, but ending the economic embargo against Cuba is up to Congress and is a long way off.

Still, the thaw in relations is real, but not without conflict and criticism.

At a town hall in Jamaica, Mr. Obama took a question rippling through the region: Why is he normalizing relations with Cuba and what does he expect to change in Havana?

"We will continue to have differences with the Cuban government, but we don't want to be imprisoned by the past," he replied.

A poll of the Cuban people out this week showed 97 percent think normalizing relations would be good. Sixty-four percent think it will change Cuba's economy, if not its politics.

The president could announce Cuba's removal from the list of state sponsors of terrorism at the summit. Cuba is one of four nations on the terrorism list, alongside Syria, Iran and Sudan, landing there in 1982 for supporting terrorists in Spain and Colombia, and harboring U.S. fugitives.

Removing Cuba from the list would allow Havana to buy weapons from the U.S. and open up access to U.S. finance.

"I think the decision has to be taken for what it is, which is an evidenced-based decision on this issue of terrorism, and a better way of defending our interests in Cuba, including our interests in supporting human rights," Ted Piccone of the Brookings Institution said.

Human rights remain a big issue in Cuba and arrests of political critics remain high. Dissidents and Castro supporters clashed in front of the Cuban embassy on Wednesday.

That's why Jose Luis Garcia Perez, known widely as Antunez, traveled here. Antunez is a prominent Cuban dissident invited as House Speaker John Boehner's guest to this year's State of the Union address. Antunez was roughed up by Castro loyalists, and told CBS News that Cuba's problems are not economic, but political. He said repression is constant and dissidents must have a seat at the negotiating table.

Antunez opposes removing Cuba from the terrorism list and what would likely come next: the opening of a U.S. embassy in Havana. He has powerful Republican friends who could legislatively try to keep Cuba on the list, but that would only provoke a presidential veto, and there's no indication Republicans would have the votes to override it.