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The Proliferation Security Initiative (PSI)


ISIAE Newsletter - CARI 
Alberto E. Dojas

July 2009

In December 2002, a merchant ship flying no flag was sailing in the Gulf of Aden. American authorities requested two Spanish warships that were following it, to search the freighter, based on the suspicion that it was carrying ballistic missiles and components from North Korea to the Middle East. The Spanish Special Forces stopped and searched the vessel about 600 miles off the coast of Yemen. Inside, 15 complete SCUD missiles, 15 missile war heads, 23 nitric acid tanks (i) and 85 barrels of other North Korean chemical compounds were found, hidden under cement bags (ii). Two days later, Yemen admitted to be the cargo´s final destination, declared that the weapons were  ligally purchased and requested the release of the ship (iii); the American and Spanish authorities allowed the ship to continue its course, after considering that there was no provision under international law authorizing the seizure of its cargo (iv).

This kind of experiences led some countries to gather in Madrid in June 2003 to establish an information exchange and coordination mechanism to restrict the illegal transport (v) of weapons of mass destruction (WMD) and its components, both by state and non- state actors (vi). Initially created by 11 states (vii), the Proliferation Security Initiative (viii) currently has 95 member states, including the recent joining of the Republic of Korea (ix); ten of them  from the Americas. (x).

PSI objectives are reflected on the "Interdiction Principles" adopted in September of 2003, that establish as subjects of proliferation concern “state and non-state actors" (xi) which are defined as "those countries or entities that the PSI participants involved establish should be subject to interdiction activities because they are engaged in proliferation through: (1) efforts to develop or acquire chemical, biological, or nuclear weapons and associated delivery systems; or (2) transfers (either selling, receiving, or facilitating) of WMD, their delivery systems, or related materials". (xii)

Notwithstanding the fact that coordinated international efforts to reinforce non-proliferation through mechanisms like the PSI were welcomed favorably by the "High-level Panel on Threats, Challenges and Change" (xiii) and the then UN Secretary General Kofi Annan (xiv), as shown in the "So San" case, actions undertaken by the PSI members may, eventually, infringe laws and principles of International Law, such, as the right to innocent passage through territorial waters and the freedom of navigation on international waters and airspace.

Interdiction measures are consistent with the international law if they are held within national borders or on vessels and aircrafts flagged at home, or if the flag State has given its consent or if a third State has been authorized by a bilateral or multilateral treaty or a UN Security Council Resolution to do so (xv). The main legal challenge for PSI members is to intercept outside its national territory (xvi) a ship or aircraft that is not registered in the state that practices the right of visit, search and eventually seizure of its cargo, even based on reasonable evidence (xvii), without the consent of the flag State (xviii) because International Conventions that regulate international maritime and air flight spaces do not allow it as a general principle (xix).

The PSI has tried to cope with these shortcomings by widening the number of participant countries; signing Ship Boarding Agreements with countries with major commercial fleets registered in their territory for the interdiction of suspect weapons of mass destruction-related cargoes (xx); new conventions (xxi) and international rugulations and UN Security Council resolutions that may allow interdiction on specific cases. As the current American Administration has renewed American support for the work of the PSI (xxii), it is reasonable to expect that initiatives aimed at the establishment of an international control system devoted to the proliferation of WMD, technologies and materials associated to their production will be encouraged. Recent Security Council Resolution 1874 (xxiii) applies the PSI interdiction principles to North Korea: it reaffirms that the proliferation of nuclear, chemical and biological weapons, as well as their means of delivery, constitutes a threat to international peace and security (xxiv): determines that the North Korean activities constitute a clear threat; calls all the member states to inspect all cargo to and from the DPRK, in their territory (xxv); to inspect vessels, with the consent of the flag State, on the high seas, if they have information that provides reasonable grounds to believe its cargo contains WMD (xxvi); and that if the flag State does not consent to inspection on the high seas, the flag State shall direct the vessel to an appropiate and convenient port for inspection (xxvii), the cargo should be seized and the Security Council duly notified about the actions taken to this end.

These actions are steps taken towards the establishment of a certain public order on the oceans and airspace, in which non-proliferation may be added to the existing regulations against slavery and piracy (xxviii). The peculiar aspect of the PSI, as emphasized by Amitai Etzioni in a recent article (xxix), is that it is, by nature, a voluntary mechanism without formal institutionalization, in which States gather to agree on policies regarding shared interests (xxx). It is a process that may constitute a model to organize global society in the years to come, in which advances would be made through a variable geometry (xxxi), that creates a new international legality. This tendency is accompanied by the Security Council, whether it is dictating resolutions under Chapter VII for specific cases or general rules through its new legislative functions (xxxii). It’s a tendency that should be carefully analyzed, since our country enjoys the eight territorial surface of the world, that includes vast maritime and air spaces.

About the author
Alberto E. Dojas is a lawyer (UBA); Master in International Affairs (Columbia University, New York); Phd. in Internacional Law (UBA). Opinions contained in this article should not be considered as reflecting an official policy of the Argentine Government.


(i) Oxidant agent used for the missile launcher.
(ii) The boat,  named “So San” and registered in Cambodia, was being followed by the American Intelligence from North Korea. Shanker, Thom. 2002. “Threats and responses: arms smuggling; Scud missiles found on ship of North Korea”. En: The New York Times, December 11; Robbins, Carla A. 2003. “Why U.S. gave U.N. no role in plan to halt arms ships”. En: The Wall Street Journal, October 21; Kirgis , Frederic L. 2002. “Boarding of North Korean Vessel on the High Seas”. En: ASIL Insights, December 12. in 1999, India captured an undeclared North Korean shipment of compound and missile plans that was headed for Pakistan, they where discovered when the boat – Ku Wol San, of North Korean insignia, was in one of the country’s western ports: “Impounded Korean ship had Scud-type missile material 1999”. En: The Indian Express, September 05. Available at: http:// www.indianembassy.org/press/New_Delhi_Press/September_1999/Impounded _Korean _Sept_ 05_1999.htm; Mohan, Raja. 2003.”India and proliferation security”. En: The Hindu, October 06. Available at: http://www.hindu.com/2003/10/ 06 /stories/ 2003100605081100.htm.
(iii) Sanger, David E. y Shanker, Thom. 2002. “Threats and responses: war materiel; reluctant U.S. gives assent for missiles to go to Yemen”. En: The New York Times, December 12.
(iv) ”There is no provision under international law prohibiting Yemen from accepting delivery of missiles from North Korea. While there is authority to stop and search, in this instance there is no clear authority to seize the shipment of Scud missiles from North Korea to Yemen. And therefore, the merchant vessel is being released”. Fleischer, Ari. 2002. Press briefing, December 11. Available at: http://georgewbush-whitehouse.archives.gov/news/releases/2002/12/20021211-5.html. For an analysis applicable to this case: Byers, Michael. 2004. “Policing the High Seas: The Proliferation Security Initiative”. En: American Journal of International Law, Vol. 98, pp. 526 y ss.
(v) The PSI could be seen as an extension of the existent transport mechanisms on transfers, such as the Group of Nuclear Supplier Countries, the MTCR or the Australia Group.
(vi) The members also agreed on the execution of joint exercises. Weisman, Steven R. 2003 “U.S. to send signal to North Korean in naval exercise”. En: The New York Times, August 18. For a list of the exercises held since the creation: http://www.state.gov/ t/isn/c27700.htm. Deterrence and containment are also a part of the PSI’s strategy.
(vii) Germany, Australia, United States, France, Great Britain, Italy, Japan, Netherlands, Poland and Portugal.
(viii) Proliferation Security Initiative.
(ix) The list of countries that are part can be consulted at: http://www. state.gov/t/isn/c27732.htm. the Argentine Republic attends the meetings since March 22, 2005.
(x)The only remaining permanent member of the Security Council to be a part of the initiative is China; Neither Brazil nor India (of the BRIC) are members.
(xi) The 1540 Resolution of the following year (April 28, 2004) defined as a non-state actor a natural person or entity that doesn’t act under the legitimate authority of a state in the execution of the activities comprehended in the present resolution, and the related materials as “ materials, equipment and technology” comprehended by the treaties and pertinent multilateral mechanisms or included in the national lists of control, that could be used for the design, development, production or use of nuclear, chemical and biological and their vector systems. The Resolution also reminisce the PSI in the tenth paragraph: Calls for all the States, as a mean to face this threat, to carry out , in conformity to their legislation and national norms and regarding international law, activities in cooperation to prevent the illegal traffic of nuclear, chemical or biological weapons and the connected materials. On this matter and the legislative character of the resolution see: Oosthuizen & Wilmshurst. 2004. “Terrorism and Weapons of Mass Destruction: UN Security Council Resolution 1540”, In: Chatham House, September.
(xii) The interdiction principles can be consulted at: http://www.state.gov/t/isn/c27726.htm
(xiii) Recent experiences with the A. Q. Khan net have shown the need and courage to take measures to stop illegal and clandestine trade of components for nuclear programs. The Proliferation Security Initiative is taking care of the problem with a voluntary character. We consider that all states should be encouraged to join the voluntary initiative. A report made by the High Level Group on Threats, Challenges and Change. A Safer World, the responsibility we share, Doc. A/59/565.
(xiv)I applaud the efforts of the Proliferation Security Initiative to fill a gap in our defenses. Kofi Annan. 2005. “Keynote address to the Closing Plenary of the International Summit on Democracy, Terrorism and Security”, Madrid, March 10.
(xv) For an analysis on the rules of procedure for marine intercepting see: Craig H. Allen. 2004. “Limits on the Use of Force in Maritime Operations in Support of WMD Counter- Proliferation Initiatives”. In: Israel Yearbook on Human Rights, 2004, pp.115-180.
(xvi) Interdiction could be applied to International terrestrial transport of merchandise.
(xvii) Weapons transport, including nuclear (and the missiles that launch them) is allowed by the United Nations Convention on the Law of the Sea, art. 23: when practicing the right of innocent passage. Though the territorial sea, nuclear powered foreign ships and vessels that transport nuclear substances or other dangerous compounds should have on board the documents and observe the special means of caution established by such cases under international law.
(xviii) June, 2003- The ship Baltic Sky (formerly registered as Sea Runner in Cambodia) was boarded by Greek officials in their territorial Waters, which discovered 680 tons of explosives and 8.000 detonators. Finally Sudan and Tunisia, declared to be the buyers of the cargo. Andrew Persbo & Ian Davis. 2004. ?Sailing into uncharted waters?. The proliferation security initiative and the law of the sea. British American Security Information Council, Research Report pp. 1-72; Al-Ahram. 2003. “Black ship' down”, 10-16 July. Available at: http:// weekly.ahram.org. eg/2003/ 646/in3.htm. October, 2003, the United States intercepted a shipment of centrifuge parts directed to Libya on board of a German Flagged ship that had parted from the Persian Gulf. The German shipowner authorized the redirection of the vessel to an Italian port. -U.S. seized shipload of nuclear equipment for Libya in October. 2004. In: The New York Times, Jan 1.
(xix) A state could plead the right to legitimate cautionary defense, which is the right to respond trough armed force to the use of illegal imminent force. The difference with legitimate defense is that the attack foreseen in art. 51 of the Charter is yet to be consummated. The legitimate cautionary defense has five variables (the classic doctrine formula; the Webster formula, the interception, anticipation and accumulation of events). If it was used, in a wider sense without the existence of an already launched attack, the variant of interception would be controversial in the present international law. The application of the Webster formula was also considered formed after an incident between an American ship that was assisting the Canadian rebels in 1837. According to this variant, to proceed with the legitimate cautionary defense the threat must be overwhelming, and leave no room for deliberation nor allow the choice of the means to respond. The application of the formula is very difficult in the current reality of commercial vessel and aircraft interdiction. See: Jennings, R. Y. 1938. “The Caroline and McLeod Cases. In: American Journal of International Law”, Vol. 32, N°1, pp. 82-99; Dinstein, Yoram. 2001. War, Aggression and Self-Defense. UK: Cambridge University Press, Cambridge. The whole question is addressed in Alberto E. Dojas: “La doctrina de la intervención preventiva”.
(xx) The agreement between the United States and Panama establishes: The Parties agree that the Government of the Republic of Panama may extend, mutatis mutandis, all rights (...) concerning vessels suspected of proliferation by sea, claiming its nationality and located seaward of any State's territorial sea, to such third States as it may deem appropriate (...). Agreements have been signed with Bahamas; Belize; Croatia; Cyprus; Liberia; Malta; Marshall Islands; Mongolia y Panama. To see the full text of this agreements go to: http://www.state.gov/t/isn/c27733.htm
(xxi) Within the frame of the OMI, the 2005 Protocols on the Convention for the Suppression of Illicit Acts against the security of maritime navigation (SUA) and its Protocol on steady platforms of 1988, Grant a legal base for the interception of WMD (see: http://www.imo.org/home.asp?topic_id=910); In the ICAO, initiatives for the penalization of transport of WMD and related materials and crimes related to air transportation. See ICAO, Special Subcommittee for the preparation of one or more instruments on new and emergent menaces: Report, Second Meeting, Montreal, February 19–21, 2008. Available at: http:// www.icao.int/ icao/ en/leb/mtgs/ 2008/ LC_SC_NET2/docs/LC_SC-NET2_ Report_es.pdf. Also: Williams, Andrew S. 2007. “The interception of civil aircraft over the high seas in the global war on terror”. Air Force Law Review; Allen, Craig H.. 2007. “Maritime counter-proliferation operations and the rule of law”, In: Praeger Publishers, June. The interdiction of proliferating transport is, in reality, one of the aspects of a larger and wider process of not necessarily institutionalized material, technology and capital flux control mechanisms regarding terrorism and WMD. See: Shulman, Mark R. 2006. The PSI and the evolution of the law on the use of force, Houston Journal of International Law, Vol. 28, N°3, pag.772 y ss; Busch, Nathan E. & Joyner, Daniel H. (ed). 2009. “Combating Weapons of Mass Destruction. The future of International Nonproliferation Policy”. In: The University of Georgia Press, January.
(xxii) ”We must also build on our efforts to break up black markets, detect and intercept materials in transit, and use financial tools to disrupt this dangerous trade. Because this threat will be lasting, we should come together to turn efforts such as the Proliferation Security Initiative and the Global Initiative to Combat Nuclear Terrorism into durable international institutions. And we should start by having a Global Summit on Nuclear Security that the United States will host within the next year”. Barack Obama, April 5, 2009.
(xxiii) The resolution declares that the members act in virtue of the Chapter VII and adopt measures under article 41 (“measures that don’t involve the use of armed force”) of the Charter. The Chinese preventions could be observed in the affirmative vote explanation: ZHANG YESUI (China): “I would like to underline that the inspection of the cargo is a complex and delicate matter. Countries must act prudently and in strict compliance of the national legislation and International law, every time there’s reasonable bases and sufficient proof. All parts must abstain of all actions or declarations that could increase the conflict. Under no circumstance must force or the threat of force must be used” S/PV.6141, pag. 3. The same question had been raised before in the debate of Resolution 1540: Hoge, Warren. 2004. “Ban on Weapons of Doom Is Extended to Qaeda-Style Groups”. En: The New York Times, April 29.
(xxiv) This qualification made by the Security Council dates January 31, 1992. See Declaration of the President of the Security Council on behalf of the members gathered in the level of Heads of State and Government, Doc. S/23500.
(xxv) ”11. Calls upon all States to inspect, in accordance with their national authorities and legislation, and consistent with international law, all cargo to and from the DPRK, in their territory, including seaports and airports, if the State concerned has information that provides reasonable grounds to believe the cargo contains items the supply, sale, transfer, or export of which is prohibited by paragraph 8 (a), 8 (b), or 8 (c) of resolution 1718 or by paragraph 9 or 10 of this resolution, for the purpose of ensuring strict implementation of those provisions”.
(xxvi) ”12. Calls upon all Member States to inspect vessels, with the consent of the flag State, on the high seas, if they have information that provides reasonable grounds to believe that the cargo of such vessels contains items the supply, sale, transfer, or export of which is prohibited by paragraph 8 (a), 8 (b), or 8 (c) of resolution 1718 (2006) or by paragraph 9 or 10 of this resolution, for the purpose of ensuring strict implementation of those provisions”.
(xxvii)”13. Calls upon all States to cooperate with inspections pursuant to paragraphs 11 and 12, and, if the flag State does not consent to inspection on the high seas, decides that the flag State shall direct the vessel to proceed to an appropriate and convenient port for the required inspection by the local authorities pursuant to paragraph”.
(xxviii) According to press information, a ship to which the 1874 Resolution could be applied to was detected, see: Sang-Hun, Choe. 2009. “Test Looms as U.S. Tracks North Korean Ship”. En: The New York Times, June 22.
(xxix)United Nations Convention on the Law of the Sea, art. 110. Today, the general rule of flag-state jurisdiction has yielded to the universal interest of combating the slave trade, piracy and drug trafficking. In future, the non-proliferation of WMD may also be added to this list: Christer Ahlström. 2005. “The Proliferation Security Initiative: international law aspects of the Statement of Interdiction Principles”. En: SIPRI Yearbook, pág. 764.
(xxx) Etzioni, Amitai. 2009. “Tomorrow´s Institution Today. The promise of the Proliferation Security Initiative”. En: Foreign Affairs, May/June.
(xxxi) Powell, Colin. 2004. “A strategy of partnerships”. En: Foreign Affairs, Jan/Feb.
(xxxii) Grégoire, Bertrand. 2004. «L’initiative américaine de sécurité contre la prolifération (PSI)». En: Défense Nationale, N°10, pp. 112-124; Winner, Andrew C. 2005. “The Proliferation Security Initiative: The New Face of Interdiction”. En: The Washington Quarterly, pp. 129-143.
(xxxiii) Resolutions 1373; 1422; 1487 and 1540 are examples of this modality unforeseen in the Charter. See, Szasz, Paul. 2002. “The Security Council Starts Legislating. In: American Journal of International Law”, Vol. 96, N°4, pag. 905; Talmon, Stefan. 2005. “The Security Council as a World Legislature. In: American Journal of International Law”, Vol. 99, N°1, pp. 179-183; Remarks by Scott, Shirley V. 2007. “United Nations Security Council Resolution 1540 and Political Legitimacy”. In: International Institutional Reform: 2005 Hague Joint Conference on Contemporary Issues of International Law, edited by Fijalkowski, A. T. M. C. Asser Press, pp. 63-67; for an analysis on the widening of the functions of the Council, see: Johnstone, Ian. 2008.”Legislation and Adjudication in the UN Security Council: Bringing down the Deliberative Deficit”. In: The American Journal of International Law, Vol. 102, N° 2, pp. 275-308.


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