Why did we use the atom bomb? What did Japan do for use to reasonable think the atom bomb would be a better idea than sending our military men?
Are you serious? Are you really that ignorant of World War II history? Oh wait, what am I thinking, you're convinced that Churchill is the one that started World War II.
Anyway, to address your rather ignorant question...
The Invasion of the Japanese Home Islands (Operation Downfall) was going to be in two parts, Operation Olympic (capturing the southern third of Kyushu, using Okinawa as a staging area. Set to begin October 1945) and Operation Coronet (invasion of the Kanto Plain near Tokyo. Set to begin Spring 1946). The geography of Japan favored the defenders because they were accurately able to figure out where the Allies were planning on invading, unlike Operation Overlord, it wasn't going to be a surprise attack.
According to the details of Operation Ketsugo (the Japanese plan for defending the Home Islands), Japan was planning an all out defense of Kyushu at the invasion beaches, including using all available civilians over the age of 10 (armed with basic weapons like spears). Japan's goal was not to defeat the Allies, it was already resigned to the fact they weren't going to win the war but rather they wanted to inflict so many casualties that the Allies were forced to the negotiating table and agree to an armistace instead of unconditional surrender.
Now, the Allies already had a taste of what was to be expected when they invaded Japan after the battles for Iwo, Saipan and Okinawa and those three bloody battles would look like a cake walk compared to the invasion of the home islands. Also, it was expected that it would take at least an additional 2 to 3 years before the total unconditional surrender of the Japanese forces on the home islands and at least a decade or more of counter-insurgency operations after their surrender.
But the major factor were the estimated casualty figures. Planners estimated that not only will all available Japanese military forces defend against an invasion, planners also figured that they would also be opposed by a fanatically hostile population. Below are some estimated casualty figures:
- A study done by the Joint Chiefs of Staff, the figures of 7.45 casualties/1,000 man-days and 1.78 fatalities/1,000 man-days were developed. This implied that a 90-day Olympic campaign would cost 456,000 casualties, including 109,000 dead or missing. If Coronet took another 90 days, the combined cost would be 1,200,000 casualties, with 267,000 fatalities
- A study done by Admiral Nimitz's staff estimated 49,000 casualties in the first 30 days, including 5,000 at sea
- A study done by General MacArthur's staff estimated 23,000 in the first 30 days and 125,000 after 120 days
- In a conference with President Truman, Gen. Marshall, taking the Battle of Luzon as the best model for Olympic, thought the Americans would suffer 31,000 casualties in the first 30 days (and ultimately 20% of Japanese casualties, which implied a total of 70,000 casualties)
- Admital Leahy, more impressed by the Battle of Okinawa, thought the American forces would suffer a 35% casualty rate (implying an ultimate toll of 268,000)
- Admiral King thought that casualties in the first 30 days would fall between Luzon and Okinawa, i.e., between 31,000 and 41,000
Of these estimates, only Nimitz's included losses of the forces at sea, though kamikazes had inflicted 1.78 fatalities per kamikaze pilot in the Battle of Okinawa, and troop transports off Kyushu would have been much more exposed.
Additionally, a study done for Secretary of War Henry Stimson's staff by William Shockley estimated that conquering Japan would cost 1.7 to 4 million American casualties, including 400,000 to 800,000 fatalities, and five to ten million Japanese fatalities. The key assumption was large-scale participation by civilians in the defense of Japan.
Now, remember that Okinawa gave the Allies a taste of what was to come if they invaded the main home islands. The Battle of Okinawa ran up 72,000 casualties in 82 days, of whom 18,900 were killed or missing (this doesn't include the several thousand Allied soldiers that later died as a result of their wounds). Okinawa is 464 square miles; to take it, therefore, cost the United States 407 soldiers (killed or missing) for every 10 square miles of island. If the U.S. casualty rate during the invasion of Japan had only been 5 percent as high per square mile as it was at Okinawa, the United States would still have lost 297,000 soldiers (killed or missing).
But for the best reason why we dropped the bomb to end the war, just ask any veteran that was slated to take part in the invasion.
ack-ack
