ATHENS — Five former U.S. secretaries of State said Thursday the next president should move quickly to close the military prison at Guantanamo Bay, Cuba.

That single act would improve America's dismal reputation in the world immediately, agreed Henry Kissinger, James Baker, Warren Christopher, Madeleine Albright and Colin Powell.

The five former secretaries, who served under Presidents Nixon, Ford, George H.W. Bush, Clinton and George W. Bush, were at the University of Georgia for a roundtable discussion billed as "The 16th Report of the Secretaries of State," which offered "bipartisan advice to the next administration." Kissinger, Baker and Powell all served Republican presidents. Albright and Christopher served Clinton, a Democrat.

Powell, who was in office when the notorious prison opened in Cuba, was the first Thursday to call for it to be shuttered. The most recent holder of the office on the stage, Powell served the current president from 2001 to 2005.

"Our image abroad has dropped significantly," Powell said. He put some of that blame on his former boss.

"Perhaps this administration has spoken a little too harshly in a unilateral way," Powell said. He added, however, that he thinks the case can be made that the administration did act in conjunction with other governments. "There are some things the new president can do right away," Powell said. "I hope the new president, and it seems it will be the case, will close Guantanamo immediately. And saying to the world [that] we are now going to go back to our traditional, respected way of dealing with people who have potentially committed crimes."

All three major-party candidates still running for president —Democrats Hillary Clinton and Barack Obama, and Republican John McCain — have called for Guantanamo to be closed.

Kissinger, who served under presidents Nixon and Ford, said that not all of the criticism of the United States is because of American actions. "Some of it is also due to structural changes going on in other parts of the world," he said.

In Europe, for example, governments no longer are the driving forces of national sentiment, Kissinger said. "European governments cannot ask their people to make sacrifices that American presidents can."

Baker, secretary of State under the senior Bush, said he thinks America's reputation is on the upswing internationally, but he was harsher than the others in criticizing U.S. policy on enemy combatants.

Guantanamo "gives us a very, very bad name, not just internationally," Baker said. "I have a great deal of difficulty understanding how we can hold someone, pick someone up, particularly someone who might be an American citizen, even if they were caught somewhere abroad, acting against American interests, and hold them without ever giving them an opportunity to appear before a magistrate."

In addition to calling for Guantanamo's closure, all five agreed that the United States should talk to its enemies, including Iran.

"We have to understand what diplomacy is really about," Albright said. "It's talking to your enemy."

The United States should not "see diplomacy as appeasement, which is what's happening," Albright said. "How we dig ourselves out of Iraq, and a bad reputation, has to do with using all the tools."

On China, most of the discussion centered on that nation's economic growth and its battles with pollution and air quality. Albright jokingly predicted that Chinese athletes will dominate the Beijing Olympics this summer, because "no one else will be able to breathe."

Kissinger, who made two key trips to China before Nixon's historic visit in 1972, said it is a "fundamental" part of American foreign policy that our attitude toward China be bipartisan.

"Every administration has substantially followed the way the relationship evolved, with some tactical variations," Kissinger said. "The main line about the importance of a close relationship has been maintained and should be maintained and will be maintained."

But that relationship, Christopher said, could change dramatically as the insular giant deals with outside forces it cannot contain.

"We need to expect more difficulty in China in the future — not to sympathize with them, but to be realistic," Christopher said. "The Internet is going to make it much, much harder to maintain the kind of control they need."