Iranian ships are increasingly flying flags of convenience, as tougher international sanctions make it difficult for these ships to do business on the open seas. The sanctions target Iran's nuclear program. They are aimed at curbing Iran's import of tools and technology that Washington suspects is aimed at nuclear bomb-making. But Iranian shippers are finding safe harbor from the sanctions -- in Hong Kong. By registering as Hong Kong companies and Hong Kong vessels, these shippers can avoid inspection hassles and delays.