This book is interesting in the way it develops all the characters of the people involved in the development of the bomb . I reads like a Frederick Forsyth novel where seemingly unrelated pieces all fall into place in the end . It seemed to start very slowly but eventually gathered pace . It reveals the anguish of some of the scientists as to whether the bomb should have been used at all even though it would clearly shorten the war and save millions of lives both American soldiers and particularly Japanese civilians . For the technically minded , a very good read .