The era of Pax Americana in the Gulf, and perhaps in the broader Middle East, is changing. Regional transformation and chaos resulting from the Arab uprisings, the rise of ISIS and its global terrorist reach, shifting US priorities around the world, and the rise of other outside powers in the Gulf have contributed to an acceleration of the transition from a Gulf security architecture with almost exclusive US access and control to a more penetrated system in which the United States is still militarily dominant. However, major powers like Russia, China, the United Kingdom, and France are more confidently stepping in, pursuing their self-interests, and assuming more expansive political, economic, and security roles that either compete with or complement US policies and interests.