Asia & the Pacific

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

"China and the United States have made remarkable strides in cooperating on nuclear security matters—in every area except the one that arguably matters most: the military sector. On March 18, shortly before Chinese President Xi Jinping arrived in Washington for the 2016 Nuclear Security Summit at the end of the month, the two countries opened a Center of Excellence on Nuclear Security in Beijing.

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.