“‘Let’s give a welcome to Macaca, here,’ Allen said. ‘Welcome to America and the real world of Virginia.‘” In a weird on-camera display of political self-immolation, Republican Senator George Allen, the fellow who once proudly sported a lynching noose in his law office, strangely resurrects a racial slur from his mother’s days in Tunisia to berate S.R. Sidarth, an Indian-American campaign worker for Democrat Jim Webb. “‘I think he was doing it because he could, and I was the only person of color there, and it was useful for him in inciting his audience, Mr. Sidarth told The Post.” Class act, Senator. Update: Has Macacagate put Allen’s seat in play?