ASEAN'security concept has three characteristics.Firstly,the unilateralism is allowed to develop under the framework of multilateralism.Secondly,the political security takes precedence in the concept of comprehensive security.Thirdly,seeking regional security and autonomy is by the great powers promise.These characteristics have significant impact on the architecture and trend of regional security cooperation mechanisms in Southeast Asia.The regional security cooperation mechanisms are showing three overlapping circles architecture.ASEAN-centr...