This doctoral dissertation develops the notion of neo-containment in the post-Cold War era. Its premise is that Cold War containment evolved to adapt to new challenges in a new era and continued to be the cornerstone of U.S. foreign policy and notably during the War on Terror and the Arab Spring period in the Middle East and North Africa (MENA). This research revisits the sizeable body of literature about the U.S. grand strategies from the early Cold War to the Arab Spring. It relies on data from official policy documents, policy makers‘ speeches, academic writings and various media resources to understand why, how and with what results the United States extended and developed the containment policy as its approach to the War on Terror and the Arab Spring. The dissertation provides a balanced account of the extent to which what we have qualified as the major Cold War mechanisms of containment continued to be implemented in comparable proportions in the post-Cold War era, but to contain new adversaries, mainly in the MENA. The United States relied firstly on economic containment which consists in using its economic power either to weaken challenging rivals by imposing economic sanctions upon them or empower allies through annual economic packages. The second mechanism of containment is the commitment to defend the U.S. ideology of ―democracy‖ which continued to be a cornerstone of neo-containment policy in the 21st century. The successive U.S presidents played the democracy cardto contain allies and adversaries. They selectively accused some authoritarian governments of abusing democracy while turning a blind eye on others. Finally, military containment reflects the American administrations‘ reliance on annual military aid and training services at consistently high levels, despite the collapse of the ‗Soviet Threat,‘ to its allies, while at the same time continuing to advocate regional proxy wars in geostrategic areas to maintain its sphere of influence.The dissertation also examines policies through the quest of primacy as U.S. ‗habit‘. It asserts, therefore, that the United States‘ political doctrines remained fundamentally unaltered despite the demise of the Soviet Union. The case study applies the dissertation hypothesis of neo-containment in U.S. foreign policy vis-à-vis the Arab Spring, to the U.S. quest for countering rivals such as Iran, by containing the newly elected Islamic governments in the Middle East and North Africa from 2011 to 2014. The Obama administration contained political Islam and Islamic parties in the Arab Spring countries as the policy response to the dilemma they posed; even though they were democratically elected, the governments represented a threat to the United States alliance system.