When plutonium was first manufactured at Berkeley in the spring of 1941, there was so little of it that it was not visible to the naked eye. It took a year to accumulate enough so that one could actually see it. Now so much has been produced that we don't know what to do to get rid of it. We have created a monster.

The history of plutonium is as strange as the element itself. When scientists began looking for it, they did so simply in the spirit of inquiry, not certain whether there were still spots to fill on the periodic table. But the discovery of fission made it clear that this...