Terrorism: Commentary on Security Documents is a series that provides primary source documents and expert commentary on various topics relating to the worldwide effort to combat terrorism, as well as efforts by the United States and other nations to protect their national security interests. Volume 142, Security Strategies of the Second Obama Administration: 2015 Developments, examines the major national security and military strategy documents released by the Obama administration during 2015: the National Security Strategy; the National Military Strategy; the National Intelligence Strategy; and the Department of Defense Cyber Strategy.This volume is intended as a sequel to Volume 137 of this series, which considered the de facto national security strategy of the Obama administration prior to the release of these documents. It is divided into four topical sections, each of which is introduced by a commentary written by series editor Douglas C. Lovelace, Jr. In addition to the documents listed above, this volume also contains recent reports analyzing those documents, as well as a legal update on the current status of the Authorization for the Use of Military Force (AUMF) and a consideration of the War Powers Resolution.