The Proliferation Security Initiative (PSI) was initiated by US President Bush on 31 May 2003. Its purpose is to prevent elements of weapons of mass destruction (WMD) from reaching or leaving states or sub-state actors of proliferation concern. Such states include first and foremost North Korea, but also Iran, the Sudan, Syria and Cuba. Countries publicly adhering to its Principles have grown from a core of 11 to more than 20, including in Asia, only Japan and Singapore.
Most WMD traffic moves by sea. The focus of the PSI is on interdictions and seizures. There have been 11 successful intercepts so far. This includes an intercept of WMD related materials to Libya that purportedly forced Libya to abandon its WMD programs. Moreover Liberia, Panama, the Marshall Islands and Croatia have signed bilateral WMD boarding agreements with the United States.
Although the PSI has made considerable progress, its aggressive promotion and implementation has created considerable controversy. It hasbeen criticized for lacking sufficient public accountability, stretching if not breaking the fundaments and limits of existing international law, undermining the UN system, limited effectiveness, and being politically divisive. Moreover, countries that are key to a successful PSI ---like China, India, Indonesia and South Korea---have not publicly joined the activity despite US pressure to do so, and Japan and Russia seem to be rather reluctant participants. Each is weighing the pros and cons of public participation.
The PSI has been cast upon already stormy political seas. In both Northeast and Southeast Asia, Cold War relationships and alliances are being stressed as the region's countriesre-adjust to each other, the United States and the new security environment. China's rise, Japan's drive to become a 'normal' country, and big power competition for influence in Southeast Asia set the political context. Within this context, maritime security issues are rising to the forefront of national concerns. Jurisdiction is creeping seaward and perceptions of threat and concepts of sovereignty are diverging, greatly elevating maritime sensitivities.
Options for increasing PSI participation and enhancing its effectiveness include changing existing international law; expanding existing conventions or developing a new one; obtaining an unambiguous empowering UN Security Council Resolution; obtaining NATO endorsement; arguing pre-emptive self-defense; and building a coalition of countries willing to perform such interdictions on each other's ships and aircraft or in or over their territorial seas. However each of these options has obstacles and limitations that must be overcome. The PSI has some ways to go before it becomes the comprehensive effective tool its founders envisioned.

Bordered by the Soviet Union, Japan, China, Taiwan and North and South Korea, the East Asian Seas contribute in a number of ways to the political and economic climate of the world. This atlas addresses vital issues in a region characterized by disputed jurisdictional claims, commercial rivalries and conflicting military interests.;The atlas provides a data base necessary for the effective solution of marine policy problems. The more than 60 maps are augmented by tables, figures and clearly stated analyses of national and transnational ocean policy disputes. With the aim of increasing "marine awareness" among policymakers and scholars of the region, the editors emphasize a regional perspective and examine the feasibility of international co-operative approaches to issues in this politically charged area.;The editors also edited "Atlas for Marine Policy in Southeast Asian Seas".