This was the first time people had to come up with a strategy to use nuclear weapons.
And it was a very small group by necessity that had the discussion, no great public debate was possible, no consultation with the great minds of the day, with philosophers and theologians and the great moralists of the time, just a few people who could only discuss it in a very closed framework.


First, every Purple Heart awarded from 1945 to this very day comes from the batch ordered in preparation for the invasion of Japan. They expected the invasion to cost a tremendous amount of lives.

Second, there was a secret deal with Stalin, if the war with Japan went beyond a certain date, the Soviet Union would declare war on Japan, but if the war could be ended before that date, the Soviet Union would have no part in post war Japan.

Third, they only had two bombs, one design had been tested once, the other design had never been tested.


Truman needed to make a decision without precedent, the reasoning went that the use of the bomb had to be dramatic, and that the second had to be used a few days later to create the impression that this would become a regular event.
In fact it would have been months before another bomb was ready.

Truman did consider the civilian casualties, and believed that civilian casualties would be reduced by using the bomb to bring a quick end to the war. Civilian casualties in the case of an invasion would have run into the millions.

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“ The subjects of every state ought to contribute towards the support of the government, as nearly as possible, in proportion to their respective abilities; that is, in proportion to the revenue which they respectively enjoy under the protection of the state.”

Adam Smith , The Wealth of Nations 1776

"We have always known that heedless self-interest was bad morals; we know now that it is bad economics"
FDR's second Inaugural Address