The world's newest country has become the U.N.'s pet project: an experiment in "nation-building." With its resilient political culture, East Timor is unusually well suited to the project. But the U.N. is finding that governing is harder than separating warring parties-especially when the country has been razed to the ground. And popular resentment is mounting. Rebuilding East Timor physically will be the easy part. Creating a democracy from scratch will be far more difficult