This is a heartstopping quote, from a recent interview on nprfreshair with Eric Schlosser—author of Command and Control. At some point everyone should read the 1946 classic Hiroshima by John Hersey just so you know.
So when you look at the destruction of Hiroshima, this major city, Hiroshima was destroyed in an instant, and 80,000 people were killed and two-thirds of the buildings in this enormous metropolitan area were destroyed instantly because 7/10 of a gram of uranium 235 became pure energy. To imagine how small of an amount that is — 7/10 of a gram of uranium is about the size of a peppercorn; 7/10 of a gram weighs less than a dollar bill.
Even though this weapon was unbelievably inefficient and almost 99 percent of the uranium had nothing to do with the destruction of Hiroshima, it was a catastrophic explosion. Nuclear weapons since then have become remarkably efficient and small and capable of destruction that makes Hiroshima seem trivial.”