Outside Mexico City’s Sports Pavilion, hundreds of young Rage fans rattle metal fences and throw rocks at the increasingly nervous police. Inside, a seething crowd of 5,000 lucky ticket holders cram into the cavernous pavilion chanting anti-government slogans and poking their middle fingers into the thick, sweaty air while waiting for Rage Against the Machine to storm the stage.One of the greatest live acts in music history, Rage only affirms that fact with this show. Whatever club, theater, arena, or stadium they’re in, the opening of each Rage Against the Machine show always feels like a grenade has gone off. But this night it was as if a truckful of bombs blew up as the band tore into the opening salvo of Testify.” Fans cascaded toward the stage like rippling waves stopping only to pogo up-and-down like jackhammers.Longtime supporters of various political causes in Mexico