經過研究聯合國在兩次波斯灣戰爭中對於集體安全制度的運用發現，聯合國集體安全制度不僅因為美國的單邊主義而使得「大國一致」的基本假設受到了挑戰，亦因九一一恐怖攻擊事件的發生，亦於如何判定對和平之威脅和自衛的界限等問題上，遇到了前所未有的困難。現今，沒有國家能夠獨立於國際社會而生存，爲順應日趨複雜的國際環境，各國更應於現有的權力結構下，透過協調與團結合作來取得共識，共同化解對於國際和平與安全的威脅。 The United Nations（UN）, as an international organization for maintaining international peace and security, in addition to acting the function of an international forum, the criterion of it is the authority of nations when they associate with other nations.In order to protect the existence and sovereignty of individual nation, the Charter of the UN clearly defines the apparatus and ways to fulfill the concept of “collective security” to be the standard to dissolve or relieve international disputes.
During the Cold War, the most crucial problem to international peace and security is the opposition of ideology between the Soviet Union and the United States, and it made the “great power unanimity” impossible to be fulfilled. Dose it mean that the collective security system will be fulfilled when the Cold War ended? This thesis takes two Persian Gulf wars as examples, through history compare method to study the process of the usage of the collective security system by the UN to maintain international peace and security, to treat the contemporary challenges of UN collective security system.
Through the study of the application of the UN collective security system in two Persian Gulf wars, we can discover that the collective security system not only faces challenge in the assumption "great power unanimity", due to the strategy of unilateralism of the United States, but also faces the unprecedented difficult in how to judge the threat of peace or the limit of self-defense right after the 911 terrorism attack. However, there is no nation can exist with isolationism, in order to adapt the gradually complicated international environment, all nations should obtain the consensus through coordination and cohesion to dissolve the threat of international peace and security together under the existing power structure.