Synopsis This book makes an objective assessment of Genesis and fall out of U.S.-U.K. military operations in Iraq beginning in the third week of March, 2003 with a multi dimensional approach. It underlines how this development marks the beginning of a new trend in American foreign policy, which not only unfolds serious consequences of unipolarism put also undermines the authority and role of the United Nations. However, that is half-truth. Almost simultaneously unipolarism has begun to be challenged by some of developed nations, France, Germany and Russia. There is something more to it. the worldwide movement and condemnation of American military operations in Iraq have begun to act as a brake on unipolarism. Above all, the United States has alienated itself from the entire Arab world some of the pro-American Arab regimes have begun to chalk out and alternative to their exclusive relationship with the United States. Saudhi Arabia’s new foreign policy trends confirm this. This implies that in the beginning of the present century to parallel developments are taking place. This book seeks to analyse these development. That is why this book merits attention of both the researchers of international affairs and policy makers.