In 1993, shortly after the fall of the Soviet Union, the U.S. and the Russian Federation signed a landmark arms-control accord. The "Highly Enriched Uranium (HEU) Purchase Agreement" called for Russia to dismantle thousands of nuclear warheads and convert the weapons-grade uranium in the bombs into fuel for American nuclear-power plants. The agreement is rarely talked about today, but it has been a huge success: Nearly 10% of all electricity in the U.S. is generated by nuclear material taken from the tips of Russian missiles once aimed at American cities.

Think about that: one in every ten lightbulbs in U.S. kitchens, Wal-Marts and baseball stadiums is illuminated by nuclear energy initially designed to obliterate millions of Americans. On Thursday, the U.S. National Nuclear Security Administration (NNSA), which monitors the dismantling of Russian weapons on behalf of the U.S. government, announced that the agreement has reached a milestone: Approximately 400 metric tons of Russian highly enriched uranium — the equivalent of around 16,000 nuclear weapons — have now been converted into low-enriched uranium, the form of the element needed to power nuclear reactors. In the vexing effort to rid the world of nuclear weapons, this little-publicized agreement provides arms-control advocates with an inspirational example of success — and a model for how to move forward.