Robert O'Hara's new play, "Barbecue" (directed with vigor and understanding by Kent Gash, at the Public), is my idea of an American classic, or the kind of classic we need. Although its fecund imagination seems unlimited, the work wouldn't exist if it didn't have the junk of our times to feed on"and spit out. Set, for the most part, in a nameless public park in the middle of the country, "Barbecue" unfolds in a kind …
