Robert Litwak, author of “Iran’s Nuclear Chess: Calculating America’s Moves,” has spent decades working on nonproliferation issues and has been following the Iran negotiations since they began. Now that a deal has been achieved, we asked him to provide a concise preliminary analysis of what it means and where we go from here.

Robert Litwak is Vice President for Scholars and Director of International Security Studies at the Woodrow Wilson International Center for Scholars in Washington. He is also an Adjunct Professor at Georgetown University’s School of Foreign Service and a Consultant to the Los Alamos National Laboratory. Dr. Litwak served on the National Security Council staff as Director for Nonproliferation in the first Clinton administration. His most recent books are Outlier States: American Strategies to Contain, Engage, or Change Regimes; Regime Change: U.S. Strategy through the Prism of 9/11; and Rogue States and U.S. Foreign Policy: Containment after the Cold War. Dr. Litwak has held visiting fellowships at Harvard University's Center for International Affairs, the International Institute for Strategic Studies, the Russian Academy of Sciences, Oxford University, and the United States Institute of Peace. He is a member of the Council on Foreign Relations, and received a doctorate in international relations from the London School of Economics.