Bruce (Peace): You wrote:

Also, the US knew the destructive power of the bombs it dropped on Japan. They had tested one at Alamogordo, New Mexico. Here. Also, thsi is the first I have heard of there being a fourth bomb. My understanding is that there was the one used at the Trinity test and the two dropped on Japan. Thank you for the info.

The Trinity Test was of a "device" which means it's a proof of concept and not designed as a weapon per se. (A few years later the first hydrogen test device would weigh many many tons, notwithstanding since then specialists have been able to reduce it in size to about the size'n shape of a large dunce cap).
The 'device' at Trinity was a plutonium weapon because it requires a sophisticated system to get the plutonium to fission without coming apart first. They did not test the uranium weapon because by its nature they were sure it would work, and uranium was slightly harder to come by than plutonium, which they were beginning to produce via breeder reactor, and once you get it started, the plutonium keeps on comin'.

So: Hiroshima: Uranium Bomb
Nagasaki: Plutonium Bomb (Actually turned out to be almost the same thing as the Alamogordo device only without the instrumentation hookups and with heavy steel streamlining containing it).
Third Bomb: There was enough plutonium for the works to a third bomb, which according to the Rhodes Book: "The Making of the Atomic Bomb" was released and available to the military, but after the results of the first two over Japan, the US government had the materials returned to the US mainland and civilian 'control.'

The nuclear 'stockpile' remained at near zero levels for a flat period after the war during which a lot of back-and-forth between government, scientists, the military, and interested civilians took place. It's too complicated for me to go into without re-reading the Rhodes book, but it's interesting.

McG of Harlow, you wrote:

The argument that the bombing of Hiroshima was justified on the grounds that it is claimed that on a balance of probabilities it caused less suffering than would otherwise have occurred in a continuing war does involve a certain logic.

But it is a logic that has some very disturbing implications. It is a logic that says that, in certain circumstances, it is justifiable to do anything, without any limits whatsoever. The only thing that matters, in the last analysis, is that the ultimate good effects envisaged will outweigh the present suffering caused. And the people who have to make that judgement are those who carry the actions involved.

Before we accept that logic we should recognise that it is a logic shared with the people who engineered the atrocities associated with Al Qaeda, and even with the architects of the Holocaust.

If we believe Hiroshima was justifiable on those grounds, our argument with those kinds of people is reduced to one about weighing good and evil effects in the balance; and while that is an important argument, underlying it is a shared understanding of ethics, which is, if the sums work out right, there is absolutely nothing which is ruled out.

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As for Nagasaki, that wasn't anything to do with ending the war, it was essentially just a way of testing a different type of atom bomb. Even on the kind of logic I mentioned just now, it was unjustifiable, and should be recognised as a war crime in every sense.

You make an appeal to logic, then circumscribe your argument around your limited use of it, to wit:
The decision to use the bomb was made by many people, among them scientists, military leaders, and lastly, the elected civilian AND military leader of the United States, Harry Truman. It was de facto a legitimate decision, and a logical decision.

But it was not only a logical decision, nor was it made only on logic. Nor should it have been.

Your general and limited setpoint of decision which I paraphrase: "do the perceived good results outweigh the other" is not a workable generalization to make equivalent the Americans, El Qaeda, and the Nazis. You could sweep under your logical carpet the Disney Coporation, Doctors Without Borders, and the planners of the Anchorage Christmas Pageant.

As for your totally illogical comment about your perception of the cause for Nagasaki, as I've mentioned in the first secton of this response, the plutonium weapon had been tested. At the time of the Nagasaki bomb, Japan had received one nuclear strike, and had not surrendered.

Chris B, (Born Again Scouser) you wrote:

If Japan had surrendered first, would the bomb have been used to end the war against Germany? Or would it have been considered less acceptable to use it against europeans (I personally think that is quite likely)?
I really liked your post. If you get into the literature of the design of the first atomic weapons, you will learn that a lot of the seminal atomic research was done in Germany by German scientists. It was fear of Germany obtaining these weapons that called into being the magnitude of the Manhattan Project. While history isn't scientific, it's my opinion that if Germany hadn't surrendered before the weapon was ready, it would certainly have been used on Germany first. I don't think racism took a role in the decision. In fact, there are records that a cultural awareness of the Japanese was practised, in that Kyoto was taken off the target list.

dianavan, you wrote:

...Many of the children who were born after Hiroshima and Nagasaki were stillborn, including my older brother. Many of my friends that were born in '47 were actually the second child. The first child was often stillborn. My father was also in the Pacific. I've always wondered how far that radiation might have drifted.

I've tried to find the exact number of miscarriages following the bomb but have been unable to find exact statistics.

Your linkage of the use of nuclear weapons in Japan and the physical effects on allied personnel you mention is without foundation. You yourself have no statistics. The war exposed many people to many conditions, climates, and chemicals. Unless the women who delivered the stillborn were involved in the war, stillbirths are unlikely to be related. Maybe you should check out the statistics at Los Alamos, where the scientists and workers on the project experienced a baby boom that got the military authorities quite disturbed.