Refugees, either because of their numbers or location, at times acquire an important political dimension. In 1989, thousands of East Germans fleeing their communist regime across neighboring countries helped topple the Berlin Wall. In the Middle East, Palestinian refugees are often used as pawns in a game of regional politics.
In 1989, the thousands of refugees who streamed out of East Germany and across neighboring countries had a big impact on the communist regimes that had to cope with their influx. Their flight alone did not cause the collapse of communism in Europe, but accelerated the process, and made it highly visible to the rest of the world. They were a catalyst for change that reshaped Europe.
Jolyon Naegele, a former VOA Vienna correspondent who has worked for more than a decade as a journalist in central and eastern Europe, says the exodus of East Germans began in the spring of 1989, when Hungary tore down the barbed-wire fence along its border with Austria.
"This [border-crossing] was then used by many East Germans. There were [Hungarian] border guards. They were no longer shooting," he said. "In the course of the summer, more and more East Germans piled into Hungary."
Thousands of East Germans also made their way to West Germany via the former Czechoslovakia. By November, the East German government opened several border crossing points in Berlin, which led to the fall of the Berlin Wall and Germany's eventual reunification.
Another refugee group whose existence has shaped the politics of an entire region for decades is the Palestinians. Hundreds of thousands of them lost their homes when Israel was created in 1948. Since then, they have been scattered in the occupied territories, throughout the Middle East and around the world.
Palestinians insist reaching a solution to their right to return to their old homes is critical to bringing about a comprehensive Arab-Israeli peace.
Richard Parker is former U.S. ambassador to several Middle Eastern countries and scholar-in-residence at the Middle East Institute.
"This is something we're not going to get to for awhile," he said. "But it's the big ape, big four million-pound gorilla sitting down at the end of the table that's going to have to be satisfied somehow."
Four million is the number of Palestinian refugees formally registered with the United Nations Relief and Works Agency for Palestinian Refugees.
Can what happened in East Germany repeat itself elsewhere? Can the estimated outflow of hundreds of thousands of North Koreans to neighboring China, for example, influence politics on a peninsula that is just as divided as Germany once was?
Katherine Newland, co-director of the Migration Policy Institute, says no. She says Pyongyang has too firm a grip on power, and is too rigid to give in to popular pressure.
"I think we all sort of look back to what happened in Eastern Europe, when there was a sudden, fairly spontaneous mass outflow of refugees to the west - the kind of pressure that that put on the Eastern European governments," she said. "We have not seen in North Korea a sort of similar susceptibility to popular pressure, even to extreme forms of popular pressure."
Refugee expert Andrew Schoenholtz is deputy director of Georgetown University's Institute for the Study of International Migration. He says the situation in East Germany was unique and not repeatable.
"It was Europe, and there was a lot of activity to move toward reform going on in different parts of Europe - not just East Germany," he said. "And the refugees were able to make a serious contribution there."
The latest U.S. Committee for Refugees count puts the number of refugees at about 13 million worldwide. Most of them, says Mr. Schoenholtz, are in a position to be exploited, but have no political clout of their own.
"By and large, what we're seeing are people who are mostly vulnerable," he said. "Remember, three-quarters of refugees are women and children. And they're mostly in vulnerable situations. They don't have the influence."
He says most refugees are still basically victims, because the international community simply doesn't care enough about their plight.