It will be months before new U.S. sanctions against Iran take hold, but global shipping operators are already pulling back from the big oil-exporting nation. The world’s two biggest shipping lines, Denmark’s Maersk Line and Swiss-based Mediterranean Shipping Co., said they were winding down general cargo shipments, while tanker owners said they plan to move their vessels to other oil-producing countries in the Middle East or West Africa. Even though the U.S. is alone in imposing the new sanctions, “I don’t think any shipping line that operates globally will be able to do business in Iran if the sanctions arrive in full force, the way they are intended,” said Soren Skou, Maersk’s chief executive. Maersk and MSC have been moving everything from electronics and household goods to food and heavy machinery to Iran. Mr. Skou said Maersk’s Iran operations are small, but with an Iranian population of 80 million, […]