Countering the Spread of Weapons of Mass Destruction

In December 2002, the United States received intelligence that a North Korean ship – the So San – was in the Arabian Sea carrying missiles destined for Yemen. The U.S. alerted the Spanish navy, which had ships in the area and agreed to intercept the ship.

The intelligence was right. Upon boarding the So San, Spanish naval personnel discovered 15 complete Scud missiles, 15 conventional warheads, 85 drums of unidentified chemicals, and 23 tanks of missile fuel, all hidden under bags of cement.

However, after a day of back and forth between the U.S. and Yemeni governments, the ship was released. The U.S. said it lacked clear legal authority to seize the missile parts.

Less than a year later, in October 2003, the U.S. and UK once again received intelligence that a ship, the BBC China, was carrying illicit cargo. U.S. government officials contacted German authorities who intercepted the ship. They found and permanently confiscated nuclear centrifuge parts destined for Libya.

The difference in outcome between these two events was no accident – it was the result of the Proliferation Security Initiative (PSI). Launched in May 2003 by eleven like-minded countries, the PSI is a global effort to prevent the spread of weapons of mass destruction.

A Global Effort

Today, there are 111 participating countries that endorse the PSI Statement of Interdiction Principles. These include committing to stopping the trafficking of WMD, delivery systems, and related materials, and enhancing relevant legal, diplomatic, financial, military, and law enforcement tools.

Although the PSI does not have any formal legal authority, the PSI has played a key role in global counterproliferation efforts for more than 20 years. PSI-endorsing countries agree to work together to impede or stop shipments of WMD-related materials to or from states and non-state actors of proliferation concern.

Many PSI-endorsing countries also have ship boarding agreements, allowing them to carry out searches and seizures of illicit material on ships originating from each other’s countries.

PSI in Africa

PSI endorsing states regularly conduct multilateral meetings, workshops, and exercises to improve their counterproliferation readiness and share best practices. One such event occurred in early February when the United States and Morocco co-hosted the 2024 Proliferation Security Initiative African Political Meeting and Outreach event. This was the largest ever PSI event on the African continent. More than 160 attendees from 35 countries attended, including 25 African countries.

During the three-day event, civilian and military leaders discussed the current state of counterproliferation, shared best practices, and emphasized the importance of continuing to expand upon nonproliferation efforts on the African continent through the PSI and similar mechanisms.

Looking Ahead

These PSI efforts are more important than ever. In recent months, several developments have shaken the global nonproliferation regime. These include:

• Iran withdrawing permission for international verification at several nuclear sites;
• DPRK continuing to develop its unlawful nuclear weapons and ballistic missile programs, and
• Russia continuing to violate nonproliferation norms by attacking Ukraine with missiles and has doubled down on its dangerous nuclear rhetoric – including withdrawing from the PSI in 2022.

However, despite the challenges posed by the current security landscape, the PSI remains strong. Following the meeting, Benin, Equatorial Guinea, Ghana, Togo, and Zambia became endorsers of the PSI, affirming their commitment to countering the spread of WMDs.

The success of the 2024 PSI African Political Meeting and Outreach event is a sign that the international community at large is steadfast in their support of counterproliferation efforts. The United States looks forward to working with the five new endorsing countries to improve our multilateral interdiction efforts and prevent the spread of nuclear weapons-related technologies.

Darby FitzSimmons is an intern in the Bureau of International Security and Nonproliferation.