Global insurers, brokers and shipping companies are concerned about an environmental catastrophe if an oil tanker sinks in the Persian Gulf. It's a massive risk in a region that stretches from Kuwait to Qatar — an area of glittering high-rise buildings, posh beachfront resorts and booming commercial centers. Its incredible wealth and shift toward tourism is a dramatic change from the late 1980s, when a tanker war between Iraq and Iran threatened the oil trade in the Persian Gulf. What the