This report analyzes defense options available to the United States in responding to current and emerging threats to U.S. security and interests in Europe, the Middle East, and Asia. It focuses on ways that the United States might adapt military instruments to meet these emerging challenges, assessing in broad terms the cost of defense investments commensurate with the interests at stake.

This report analyzes the U.S. and allied campaign against the al Qa’ida–linked terrorist group al Shabaab in Somalia, examines what steps have been most successful against the group, and identifies potential recommendations. It concludes that, while al Shaba'ab was weakened between 2011 and 2016, the group could resurge if urgent steps are not taken to address the political, economic, and governance challenges at the heart of the conflict.

This report examines the status and evolution of al Qa’ida and other Salafi-jihadist groups, and uses qualitative and quantitative data to assess whether this movement has strengthened. The author uses this analysis to examine U.S. strategic options to counter al Qa’ida and other terrorist groups based on the threat level and the capacity of local governments.

The Islamic State has lost substantial amounts of territory but continues to conduct and inspire attacks around the world. This report assesses the threat the Islamic State poses to the United States and examines strategies to counter the group and prevent a resurgence of the Islamic State or other Salafi-jihadist groups.