The United States has maintained a robust military presence in the Gulf since the days following the 1977 Carter Doctrine, a presence that assumed its current shape more or less in the wake of the 1990–91 Gulf War. Successive U.S. administrations have preserved that presence primarily for twin strategic purposes: to prevent another regional war (long assumed to be an Iraq-centered contingency), and to blunt the rise of an aggressive and anti-U.S. hegemon (an Iran-centered scenario), both for the chief intent of protecting the reliable flow of Gulf oil to the U.S. and world economies. That is why the term “dual containment,” coined by the Clinton Administration in 1993, aptly described U.S. policy for a good part of the 1990s. Since the ouster of the Iraqi Ba‘ath regime in 2003, the Islamic Republic of Iran has constituted the greatest challenge to U.S. interests in the Middle East and the stability of the regional order, notwithstanding the civil wars in Iraq and Syria and the rise of the Islamic State in their wake. Read the full article here.