The just-concluded fourth and final nuclear security summit saw some serious progress, but also some missed opportunities.

More than a decade after its nuclear security recommendations first recognized the threat insiders pose to nuclear facilities, the International Atomic Energy Agency (IAEA) has finally released its guide on nuclear material control and accounting for nuclear security.  (This has been in the works for years.) Many people wrongly think that any material under international safeguards has accounting and control good enough for security purposes as well, but there are important differences.

In The Hague, leaders have agreed on a new initiative to secure dangerous radiological sources that might be used in a so-called “dirty bomb” – to prevent incidents like the December 2013 theft of a truck carrying a deadly source in Mexico.

So what did the nuclear security summit in The Hague accomplish?  A good deal.  Despite being overshadowed by the crisis in Ukraine and the associated crush of side meetings, the summit in The Hague once again served as a forcing event to cut through bureaucracy and get important decisions made.  Just as having friends over for dinner motivates you to clean up your house, going to a major global summit motivates leaders to push their bureaucracies to give them something worthwhile to talk about when they get there.

Today, the United States and Japan announced that Japan would eliminate all the plutonium and highly-enriched uranium at its Fast Critical Assembly (FCA) at Tokai-mura.  This is a tremendous step forward for nuclear security; for terrorists, this would be some of the best material that exists in any non-nuclear-weapon state.  The material includes 331 kilograms of plutonium, most of it weapons-grade, and 214.5 kilograms of weapons-grade HEU.  (The FCA also includes over a ton of material just at the 20 percent U-235 mark that defines HEU.)   The weapons-grade HEU is enough for four simple terrorist “gun-type” bombs or a larger number of trickier-to-build implosion bombs.  The plutonium amounts to more than 40 bombs worth of material.

On March 24-25, leaders from around the world will gather in The Hague for the third nuclear security summit.  What should we expect the summit to accomplish? Overall, the summits have already transformed the international nuclear security discussion, elevating the topic from the bowels of governments to presidents and prime ministers, motivating states to make decisions to upgrade security, increasing understanding of the nuclear terrorism threat, and getting thousands of people around the world focused on improving nuclear security.  But that progress may come more from the process than from the pageantry of the summits themselves.