For years after World War II, the Jewish genocide was ignored, forgotten, or misunderstood. What changed? — By Tim Gihring Rachel McGarry remembers the moment she began to understand the Holocaust. It was 1981. She was a kid turning cartwheels in a friend’s suburban basement, with the television on. Suddenly, a woman onscreen began recounting her imprisonment in Nazi concentration camps. “It was gripping,” says McGarry, who…