Ahead of next year’s Apec summit, Vietnam has a grand plan to transform Phu Quoc, its largest island, into Southeast Asia’s leading conference and exhibition hub.The 137 trillion dong (US$5.2 billion) blueprint includes an airport overhaul, a light-rail line, clusters of luxury hotels and a brand-new sewerage system – much of it paid for by one of the country’s largest conglomerates, in return for tracts of land, operating concessions and the cachet of building national landmarks.But problems...