Controversy over a proposed Islamic cultural center in New York City appears to have stoked an increase in hate crimes and other bias incidents directed at Muslims in America, according to congressional testimony submitted today by Southern Poverty Law Center President Richard Cohen.

This report on the history of the Ku Klux Klan, America’s first terrorist organization, was prepared by the Klanwatch Project of the Southern Poverty Law Center. Klanwatch was formed in 1981 to help curb Klan and racist violence through litigation, education and monitoring.

The number of active hate groups in the United States topped 1,000 for the first time and the antigovernment “Patriot” movement expanded dramatically for the second straight year as the radical right showed continued explosive growth in 2010.

A year ago, we introduced a new school curriculum, Civil Discourse in the Classroom and Beyond, with this urgent call: "There is a pressing need to change the tenor of public debate from shouts and slurs to something more reasoned." The tragedy in Tucson this weekend reminds us that it's a call that politicians and pundits would do well to heed.