The number of hate groups operating in the United States continues to rise, according to the Southern Poverty Law Center, which has tracked such groups for 30 years. Fed by dislike of President Obama, changing racial demographics, and the growing gap between rich and poor, the number of hate groups and antigovernment organizations grew to 1,018 last year. Antigay groups grew especially quickly, to 27 from 17 in 2010. Antigovernment and militia groups also grew quickly. The center found 1,274 of such groups, up from 824 last year. “They represent both a kind of right-wing populist rage and a left-wing populist rage that has gotten all mixed up in anger toward the government,” said the director of the center.