Where Lifton and Mitchell quote a sentence fragment from a memo, Alperovitz quotes several paragraphs and then the reply to it. If Bess had cabled Harry to pick up a loaf of bread on the way home from Potsdam, Alperovitz's readers would be able to factor that in. I don't mean to knock such thoroughness, just label it. The years Alperovitz spent compiling these details were important. His book is surprisingly well-written and easy to read given what it is--but what it is means that he often has to slow down to the plodding pace of the people he's tracking.
Both books make an important point about the asserted life-saving benefits of the bomb. Truman--who was determined to get "unconditional surrender" from Japan as he had from Germany--rejected advice to offer to let Japan keep its emperor. That seems to have been the sticking point that blocked Japanese leaders who wanted to lay down arms earlier.
Yet Truman agreed to that very condition when Japan surrendered the day after the Nagasaki attack. Alperovitz calculates that 10,000 U.S. soldiers died in the Pacific in the three months Truman took to change his mind about the emperor.
Like the Lifton/Mitchell book, the Alperovitz book belongs on every library shelf, if only to be dropped on the foot of anyone who accuses Lifton and Mitchell of occasional flights of fancy or omitting some context. Between them, they pull back the veil from a 50-year black hole of history.