The article "10. Foreign Policy" explores different ways to understand how countries interact with each other. It looks at theories and methods for analyzing foreign policy, which is how nations handle their relationships with other countries. The researchers examine different levels of analysis, from the big picture of the international system to individual decision-makers. They use the Gulf War as a case study to show how these approaches can be combined. The article also mentions the important role of experts and think tanks in studying foreign policy.