International Security & Defense

Europe after the Russo-Ukrainian War must develop a new security structure to defend against any Russian aggression. The safest option is a non-offensive, confidence-building defense. This option includes proposals such as the “spider in the web” strategy and the “porcupine” strategy to provide for European security in a region threatened by Russian expansion—without relying on the threat of nuclear war. 

Dozens of in-depth interviews in Lebanon after its civil war show how wartime displacement transformed localities in ways that transcend religious identity. With more than 80,000 people displaced from southern Lebanon because of fighting since October 7, 2023, the Israel-Gaza war is likely to strengthen Hezbollah’s grip when the displaced populations return and in localities in south Lebanon where displaced populations settle. 

Christopher Darnton responds to Rachel Metz's Winter 2022/23 article, "The Cult of the Persuasive: Why U.S. Security Assistance Fails."

This piece is a series in the Defense, Emerging Technology, and Strategy (DETS) Program’s analysis on the war in Ukraine, including a corresponding policy brief on Ukraine’s Battlefield Technologies and Lessons for the U.S. published in July 2023. 

On October 30, 2023, President Biden issued the Executive Order on the Safe, Secure, and Trustworthy Development and Use of Artificial Intelligence, aimed at realizing the benefits of AI, while mitigating critical risks. This article provides an overview of its key national security initiatives and explores issues relevant to implementation.

For Ukraine to maintain its defense and decisively thwart Russia’s invasion, it will take steadfast commitments from Western allies providing both state-of-the-art equipment and basic warfighting needs, local industry leaders and factory workers readying equipment for the frontlines and developing innovative technologies, and civilian volunteers tirelessly filling in the remaining gaps.

Peaking great powers facing a slowdown in growth are likely to try to violently shake up the world. These findings amend classic theories of great power conflict. They help explain some of the most consequential geopolitical events in modern history. And they have ominous implications for contemporary Chinese foreign policy. 

Climate disasters shape the trajectory of internal conflicts in states highly vulnerable to changes in conflict dynamics. Conflict after a climate disaster escalates when the disaster induces shifts in relative power that enable one side to increase its military efforts. But when one actor is weakened by the disaster and the other lacks the capability to exploit that weakness, conflict intensity declines.

State support to non-state armed groups outside a state’s own territory is commonly seen as a direct relationship between a state sponsor and a rebel group. But powerful states can use a third state—a dealer or broker—as a conduit for military and other support. States that fail to identify an alignment of interests with these intermediary dealers and brokers face strategic failure.

Around the world, the United States relies heavily on security assistance to gain influence and make its allies more formidable. When actual war breaks out, however, many long-time recipients of such assistance fight poorly or otherwise do not seem to have heeded the lessons that U.S. trainers tried to impart. The Naval War College’s Rachel Tecott Metz examines this track record, arguing that the United States relies too much on teaching and persuasion and should instead emphasize conditionality more.