Twenty eighteen was a disquieting year. Although capitalism continued to raise living standards almost everywhere, the geopolitical outlook dimmed. An antimarket backlash gained strength in many countries, and relations between the U.S. and China continued on a downward trajectory even as global defense spending hit a record high.

Some leaders thrived in this environment—either despite the geopolitical headwinds or because of them. Here are the five men who, for better in some cases and worse in others, were the biggest winners...