GUERRILLAS by V.S. NAIPAUL 248 pages. Knopf. $7.95.
Three burnt-out cases smolder on a Caribbean island. Roche, 45, is an altruistic white whose support of black causes once earned him torture in a South African jail. Now he is the house humanitarian for a local corporation, supervising a back-to-the-land project. Its design: to drain revolutionary energy away from foreign investments and native rulers. Jimmy Ahmed, a racial mix of yellow, black and white, runs this sham commune as a means of assembling responsive young boys; his heart is back in London, where trendy liberals once puffed him up from criminal to...