A stagnancy seems to have beset the reggae world in the years since Bob Marley's death in 1980, with the scene drifting gutless in a ganja-tranquilized haze of Jah muzak while various pretenders to Marley's past eminence ape each other's unoriginality, all growing less interesting by the minute. Enter Alpha Blondy, who comes to us not from Jamaica but from Africa's Ivory Coast, and whose new album on Shanachie, Apartheid Is Nazism, is one of only three or four roots reggae LPs I've gotten genuinely excited about in this decade. The secret is simple: like Marley (and unlike most reggae artists who've come up recently), Blondy understands that all the rhythm vamps and dub mixes and rasta jive in the world can't substitute for the ability to write a catchy, well-focused song. Crooning in no less than five different languages, Blondy gets straight to the point, laying out his sociopolitical convictions bluntly but infectiously (if you have something important to say, say it well). Having churned up big waves already in Africa and Europe, Blondy is now making his wry first assault on the U.S., so look out. Tonight, Biddy Mulligan's, 7644 N. Sheridan; 761-6532.