THE WORLD'S ARTISTS and writers have always found haven in San Francisco. Cultural fusion has thrived in Baghdad by the Bay for generations, and leave it to the San Francisco Ethnic Dance Festival to show how it's done. First saw the festival in the '80s. Caught up with this past weekend's show, and the dancers and musicians continue to amaze. Diversity, ethnicity, otherness no longer typecast their work. Boundaries blend. Beats merge, rhythms synch. They simply are performing artists of a high order. All excel. My favorites: The mash-up of Indian dance (Abhinaya Dance Company of San Jose) and Japanese taiko drumming (San Jose Taiko), and the high-energy twirling and foot-stomping of Ballet Folklórico Mexicano de Carlos Moreno and the Diamano Coura West African Dance Company. Is a global aesthetic emerging? If so, it'll happen in the dank streets and dark retreats of S.F. -- and New York, L.A., London. Elitist critics won't get it for decades. So polyglot, multicult, millenial creatives will need to root it out, define it, delineate it as we speak.