http://www.randomhouse.com/catalog/display.pperl?isbn=9780375414138&view=excerpt
An excerpt of this excellent book has been made available on the Random House website.
It is the third part of a non fiction trilogy about the development of nuclear weapons / power and the ensuing cold war arms race the first part of which won the Pulitzer prize.
After reading the chapter I immediately bought the first book (The Making Of The Atomic Bomb) from Amazon though I had to import it from Canada as it is no longer in print!