The US operated reactors to produce weapons plutonium at the Hanford site in Washington state and the Savannah River site in South Carolina. The last Hanford re

The US operated reactors to produce weapons plutonium at the Hanford site in Washington state and the Savannah River site in South Carolina. The last Hanford reactor making weapons plutonium shut down in 1987 and the last of the Savannah River plutonium reactors shut down in 1988. Commercial power reactors like those used for electricity in the US produce plutonium that has an isotopic composition unfavorable for weapons. It has more plutonium 240 than weapons grade material. The high spontaneous fission rate of Pu-240 makes it difficult to produce reliable weapons that reach full yield without pre-detonation. It's fair to criticize the US for holding on to its old stockpiles of weapons plutonium. It's not sensible to criticize it for continuing to make weapons plutonium, because it hasn't done that in 30 years.