When Puerto Rico took the Dream Team by storm on Sunday, the victory was one of the biggest upsets in international competition – even if all the competitors are American citizens.

Of the 202 countries competing in the Olympics, about a dozen are not independent nations, such as Hong Kong, the U.S. Virgin Islands, and American Samoa. Most were admitted during the Cold War, when the International Olympic Committee was trying to increase its membership.

“There appears to be no logic behind it, except tradition,” an Olympic Historian, David Wallenchinsky, said of how the committee determines nationhood. “One always assumes that a nation is internationally recognized and has the option, unless it’s extremely small, of being a member of the U.N, but Guam, Puerto Rico, Samoa – they don’t qualify, but here they are in the Olympics.”

According to the Olympic Charter, each competitor must be a national of the National Olympic Committee that is entering him or her. If an athlete is a national of two countries, he or she is expected to choose between the two. Once a team is chosen, if an athlete wants to switch nationalities, he must spend three years as a legal resident in the new country – regardless of state.

For Puerto Rico, which was admitted by the Olympic Committee in 1948, the hazy line of American citizenship and Puerto Rican nationhood in the international competition is a perennial issue.

In 1976, a Puerto Rican-native, Butch Lee played basketball for Marquette University. When the Marquette coach was allowed to choose one player for the Olympic team, according to Wallenchinsky, he did not choose Lee.

Not satisfied with the choice, Lee returned to his native Puerto Rico and led that national team to within one point of beating the American team for the gold.

A tennis player, Gigi Fernandez, represented Puerto Rico in international competitions in Central and South America. But when it came time for the 1992 Olympics, she played for America, much to the chagrin of the island.

“There was like a little riot in the island,” said the president of the Puerto Rican Olympic Committee, Hector Cardona. “But according to the rules she can do it.”

Similarly, Cardona said, there was nothing the committee could do when Denver Nuggets star Carmelo Anthony, made the decision to play for the American team.

“We agreed with that because everyone can decide for themselves,” Candona said.