Here you go core -
They also say that Truman should have chosen one of the several available ways to compel a Japanese surrender without an atomic bombing of two cities. The most obvious alternative is an American invasion of Japan. Olympic was the code-name given to the planned American invasion of Kyushu, one of the four Japanese home islands, if an atomic bomb were not available by late October. Two separate estimates exist to rate the number of American casualties that would result from such an invasion. A joint war plans committee comprised of the army and navy came to the conclusion that 46,000 Americans would die in an invasion of Kyushu and later Honshu. The number of American wounded averaged three to one during the later years of the war, so according to this estimate, 175,000 American casualties were not out of the question. However, these figures were based on such tentative intelligence that George Marshall, the army’s chief of staff, bluntly rejected them.
A second estimate proposed by Admiral Leahy was much higher. The invasion of Iwo Jima caused 6,200 American deaths, and the U. S. outnumbered the Japanese by four to one. Okinawa cost 13,000 U. S. servicemen, and they outnumbered the Japanese by two and one-half to one. These 13,000 men made up more than 35% of the U. S. landing force. Consequently, Admiral Leahy came to the conclusion that it was absurd to think that any less than 35% of the American force that invaded Japan would be killed. Based on the estimate of 560,000 Japanese soldiers on Kyushu as of early August, Leahy predicted that at very minimum over 250,000 American soldiers would lie dead as a result of an invasion of the Japanese islands.
It was later found that the troop strength on Kyushu was greatly under-estimated, and that by August 6 the Japanese had over 900,000 men stationed on Kyushu, nearly twice as many as thought. Leahy’s estimates that the Americans would have a preponderance, when in fact the 767,000 American soldiers who would comprise the landing force were already greatly outnumbered three months before Operation Olympic was actually to begin. By November, Japanese troop strength could easily double or triple, making between 500,000 and 1,000,000 American deaths conceivable.
These numbers do not even begin to account for the Japanese dead. In Okinawa, twice as many Japanese were killed as Americans. It is therefore plausible that between 100,000 (according to the earliest estimate) and two million soldiers would die in an invasion. This number does not include Japanese civilians dead, which could conceivably have been even higher than the number of dead soldiers.
The Japanese army was already training its civilians to fight with sharpened bamboo poles. According to samurai tradition, there was no more honorable way to die than to do so for Japan and the emperor, and the civilians were quite prepared to take this philosophy to heart. Using sharpened pikes the Japanese could easily prevent a military government from being effective in those towns which the U. S. captured. Futher, and even more brutal, was the training of young children to be “Sherman carpets.” Japanese children were to be strapped with TNT and throw themselves under American tanks, thereby dying in the most honorable way possible--by killing the enemy. It can be assumed that at least as many civilians would have died as soldiers, bringing the totals somewhere around 200,000 to four million Japanese dead, along with the 50,000 to one million American dead, totaling 250,000 to five million total dead.
This can found at
http://oror.essortment.com/presidenttruman_rywp.htm