International Security & Defense

Stephen Walt argues for a return to a realism-based U.S. grand strategy.

Why did the United States withdraw from Lebanon in February 1984? How did new information shape policymakers' proposals to expand, maintain, or terminate the intervention? Drawing upon declassified records, the authors challenge the conventional narrative that the October 1983 barracks bombing precipitated the American withdrawal from Beirut.

This article presents both the fundamental changes that have taken place in Israel's strategic environment, from conventional, state-based threats to primarily asymmetrical ones, and the responses it has developed to date. It also addresses Israel's relations with the United States and other primary international actors, as well as Israel's nuclear and regional arms control policy.

Chuck Freilich writes that the Syrian conflict has triggered Israel's primal fear: the threat of an entrenched Iranian presence on its borders. If a resurgent, unreliable Russia doesn't step in, then Assad and his army will be Israel's first targets.

Iran has been a critical player in the Syrian war since 2011, crafting a complex foreign policy and military strategy to preserve its Syrian ally. What have been the drivers of Iranian decision-making in this conflict? And how has Iranian strategy evolved over the course of the war? This article argues that the logic of deterrence has been fundamental not just for shaping the contours of Iran–Syria relations since the Islamic Revolution of 1979, but also for determining the overall trajectory of Iranian strategy in the Syrian war. The authors outline Iran's decision-making calculus and divide the country's strategy on Syria after the Arab Spring into four primary phases: 1) a ‘Basij’ strategy to establish local militias in Syria; 2) a regionalization strategy to incorporate transnational fighters and militias in the war effort; 3) an internationalization strategy to incorporate Russia and balance the United States; and 4) a post-ISIS deterrence strategy to balance against the United States, Turkey and Israel. Iran's Syria strategy progressively escalated in response to the possible defeat of its ally and the deterioration of its forward deterrence capacities against the United States and Israel. Today, the potential for direct inter-state conflict is rising as proxy warfare declines and Iran attempts to maintain the credibility of its forward deterrence.

Trump administration claims of progress in talks with the Taliban have sparked fears even among the president's allies that his impatience with the war in Afghanistan will lead him to withdraw troops too soon, leaving the country at risk of returning to the same volatile condition that prompted the invasion in the first place.

Stephen Walt lists eight reasons that Washington has repeatedly made the mistake of making promises around the world it can't keep.

Stephen Walt offers a crash course in international affairs for Washington's newest arrivals.

Harvard Kennedy School’s Belfer Center for Science and International Affairs has named General (ret.) Lori J. Robinson a non-resident Senior Fellow. After 37 years of military service, Gen. Robinson retired this year as Commander, United States Northern Command and North American Aerospace Defense Command.