Lost world: a new traveling exhibition explores the Nazis' brutal destruction of Germany's once-thriving gay community. (culture).

Nazi Germany not only devised the pink triangle symbol and killed thousands of gay men but also decimated that era's world center of gay life. A half century later, that news seemingly has yet to reach most of America.

The U.S. Holocaust Memorial Museum in Washington, D.C., hopes to change that with "The Nazi Persecution of Homosexuals 1933-1945." So far, seven U.S. cities have signed on to display over the next two years the reproductions of 250 photographs and documents that explain the persecution of German gay life during the Nazi regime.

"Berlin had been the base of the world's gay rights movement--there were more lesbian bars in Berlin before Hitler than there are now," says James Lichti of the Los Angeles Museum of the Holocaust, host of the exhibition through July 11. "The Nazis viewed homosexuality as a sickness linked to a Jewish plot to weaken Aryan men."

More than 100,000 gay men (lesbians were not deemed a threat to society) were arrested, and some 50,000 sent to prison, concentration, or work camps to be "cured" by a regimen of hard labor. In reality, the men shipped off to these camps faced a life expectancy of about three months. Some were subject to castration and other medical experiments.

The U.S. Holocaust Memorial Museum plans similar exhibits on all of the Nazis' non-Jewish victim groups; they chose the persecution of homosexuals first because of the amount of documentation available and because of strong interest from the gay community.

"Much of this is about being vigilant about intolerance and stereotypes," says exhibition curator Edward J. Phillips. "We're trying to make people aware of casting out entire social groups based on generalizations and discounted individuality."

Karlin has written for The New York Times, Forbes, and Newsweek.