This seems like a bit more than an accounting error:
Enough plutonium to make dozens of nuclear bombs hasn’t been accounted for at the Los Alamos National Laboratory in New Mexico and may be missing, an activist group says in a new report.
There is no evidence that the weapons-grade plutonium has been stolen or
diverted for illegal purposes, the Institute for Energy and Environmental
Research said. However, the amount of unaccounted-for plutonium — more than 600 pounds, and possibly several times that — is so great that it raises “a vast security issue,” the group said in a report to be made public today.
“Vast” is right. As much as 660 pounds is unaccounted for, and the bomb that flattened Nagasaki was built with only 13 pounds of plutonium. Sleep well!