The Proliferation Security Initiative

The United States launched the Proliferation Security Initiative (PSI) in 2003 to help curb the proliferation of weapons of mass destruction (WMD). Since then, PSI membership has expanded sevenfold, and the program has contributed to significant seizures of WMD shipments.

Last updated October 19, 2006

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On December 10, 2002, acting on a tip from U.S. intelligence, a Spanish warship on patrol in the Indian Ocean as part of the U.S.-led war in Afghanistan stopped the So San, a North Korean cargo ship en route to Yemen. In the ship’s hold, hidden amid 40,000 bags of cement, inspectors found fifteen scud missiles armed with conventional warheads. Though dangerous, the cargo was not illegal, and Spain lacked the legal authority to seize the weapons. The following day the Spanish allowed the So San to continue its voyage. The Spanish navy barely had the authority to stop the ship in the first place: Under international maritime law a ship on the high seas may only be searched if it is without nationality, or if it is stopped by the nation with which it is registered. Spanish officials were only able to board the So San because the vessel had numerous problems with its registration and other paperwork.

This incident was among the factors that prompted the Bush administration to launch the Proliferation Security Initiative (PSI), an effort aimed at stopping the spread of weapons of mass destruction (WMD) and related materials. The initiative seeks to coordinate governmental nonproliferation activities around the world in the face of advanced communications technologies and expanding global trade that have facilitated the smuggling of WMD.

What is the PSI?

Launched by President Bush on May 31, 2003, the PSI is an attempt to curb the spread of chemical, biological, and nuclear weapons. The PSI is not a formal organization; it does not have members, a charter, or offices. Rather it has "supporters"—currently more than seventy nations—who are encouraged, not required, to commit to a Statement of Principles, to strengthen and enforce their own nonproliferation laws, and to participate in training activities and actual interdiction operations. Initially a group of core members, meeting separately, helped establish the PSI and facilitate its expansion. But amid concerns over a lack of transparency, the core group disbanded. Nations are willing to support the PSI in part because their support does not bind them to any decisions: There is no larger body making judgments on behalf of the supporters, and nations decide on a case-by-case basis whether they will participate in an exercise.

The PSI was conceived and promoted under the oversight of John Bolton, then U.S. under secretary of state for arms control and international security, with the goal of building cooperation among nations in order to facilitate the interdiction of shipments of WMD materials. "We needed a tool to stop the transfer of this kind of technology," explains Amy Gordon, a former State Department official who led diplomatic coordination of the PSI.

How does the PSI work?

Members of the Bush administration have repeatedly emphasized that the PSI is "an activity, not an organization." As Bolton told the House International Relations Committee in 2004, PSI nations "create a web of counterproliferation partnerships through which proliferators will have difficulty carrying out their trade in WMD and missile-related technology." These nations often toughen and enforce their own domestic laws regarding WMD and related materials. Since much of international maritime law defers to national law in such cases, this strengthening helps facilitate future interdictions. To that end, the United States has begun negotiating bilateral ship boarding agreements with several nations, including Panama and Liberia, which have large ship registries. These agreements simply establish a framework for communicating in the event the United States does want to board a ship; they do not grant advance approval, nor do they grant any authority to seize cargo.

The most high profile PSI activities are the interdictions themselves. Military and law enforcement personnel from various PSI nations convene periodically for training exercises to practice different scenarios for interdictions. When a country has a concern over a potential WMD shipment, it notifies the other relevant nations, which then track the shipment, and if possible, intercept it.

What nations are major supporters of the PSI?

Ten other nations joined the United States at the inception of the PSI: Australia, France, Germany, Italy, Japan, the Netherlands, Poland, Portugal, Spain, and England. Of the dozens of nations that have since pledged their support, Russia is perhaps the most significant. Notably absent is China, though in a 2004 press conference Bolton told reporters, "We have had some operational cooperation with China in interdiction activities." However, in the past China has been accused by the United States of exporting weaponry to Pakistan as well as the rogue regimes in North Korea and Iran.

What legal authority does the PSI have?

None. The PSI operates under preexisting legal norms, and its interdiction principles state that all activities are to be "consistent with national legal authorities and relevant international law and frameworks." At times this can prove problematic: As described above, maritime law generally allows ships free passage. To get by this, PSI nations are often forced to resort to the so-called "broken tail-light scenario," in which officials exploit all possible legal means for stopping and searching a ship. Thus the U.S. interest in bilateral ship boarding agreements.

A ship’s right to free passage is not the only obstacle to searching a vessel on the high seas. Experts say the way cargo containers are stacked on boats makes opening them on the open water very difficult. In such scenarios, ships may be diverted to a nearby port. This not only facilitates the physical search, but the legal effort as well. When at port, ships are bound by the laws of the host nation, hence the PSI emphasis on strengthening domestic regulations.

This port tactic was employed by a group of PSI nations in October 2003 when they intercepted the German-owned BBC China as it steamed through the Mediterranean Sea from the port of Dubai en route to Libya. U.S. and British intelligence believed the boat was carrying illegal cargo and contacted German and Italian authorities. Germany instructed the ship’s owner to have the boat diverted to the Italian port of Taranto. In the hold, inspectors found nuclear centrifuge parts destined for Muammar Qaddafi’s regime from the nuclear-technology smuggling network of Pakistani scientist A.Q. Khan. The seizure helped unravel the Khan network and was a major factor in negotiating the forfeiture of Libya’s WMD programs.

Is the PSI effective?

Though the BBC China incident was a success, it was not solely a PSI operation; other groups investigating Libya and the Khan network also contributed to the interdiction. Nevertheless, Bush administration officials have cited it as an example of the PSI’s impact. Still, the PSI’s effectiveness is difficult to gauge, in part because the measures for its success are somewhat nebulous.

The most high-profile PSI activity, interdictions, is one indicator of PSI success, but due to the secretive nature of these operations, there is little data publicly available. Speaking on the second anniversary of the PSI, Secretary of State Condoleezza Rice announced that in the previous nine months the United States and its PSI partners successfully carried out eleven interdictions. Yet these numbers carry little meaning, and critics of the PSI question how many of these interdictions would have happened without the PSI.

Another important function of the PSI is its ability to discourage shipments of WMD materials. Though there is no real measure of this either, Gordon, the former State Department official, insists the PSI "is serving as a very useful deterrent."

Michael Levi, CFR’s science and technology fellow, says an area where the PSI has been successful is in its less acknowledged role of fostering better relationships and communication with other nations. Experts say some nations were initially cautious about joining the PSI, concerned it might draw them in to an organization that endorsed legally questionable activities. But as time passed, the PSI’s loose affiliations and respect for international law has won it more supporters. "It’s been effective," Gordon says, "It doesn’t have a perfect record, but this issue is too important for us not to do all we can in every arena."

How can PSI be improved?

"They still need to find some way of getting explicit authorization for interdiction on the high seas," Levi says. This may be a difficult battle to win, as most nations will not be willing to subject their ships to search unless on a case-by-case basis. One way around this is to win the support of countries controlling well-trafficked ports and canals, where there is no question of jurisdiction. Continuing to encourage PSI expansion increases PSI nations’ collective authority to search ships around the world. In the wake of North Korea’s first-ever nuclear test, U.S. officials ramped up pressure on Seoul to increase South Korea’s participation in PSI activities.

The PSI could begin targeting financial channels as well. At a meeting of PSI nations in Warsaw in June, 2006, Robert G. Joseph, the current undersecretary for arms control and international security, expressed a need for "tools to interdict payments between proliferators and their suppliers."