Exact Answer: 120 to 125 days
Operation Downfall is the execution of the planning invasion of Japan. This operation has two parts, which were signed subsequently as Operation Olympic and Operation Coronet. Japan’s collapse by mid-1945 was transparently visible that it was not that far.
There had to be a solid plan by its allies for intruding the mainland of Japan, also knowing the consequences of costing lives in many numbers. The military commanders of the American army were given the job of planning that brutal invasion. These military commanders included Chester Nimitz, Happy Arnold, George Marshall, Douglas MacArthur, and Ernest King.
How Long Would Operation Downfall Have Taken?
| Process | Time |
| End of Operation Downfall | 120 Days |
| End of Casualty Survey | 125 Days |
Some pieces of evidence tracked down to a conclusive point that an invasion on the mainland of Japan will turn into a bloody matter of concern if each one of them. The complex aspect related to such a type of attack also led the US army to develop alternative plans to be the best of them. An air campaign would do the work supporting a blockade that was to be executed by the navy.
The US military was ready with their plans to invade Japan by launching bombs using airbases present in China. The military believed that this campaign might take more time and the public of America would get the suffering as morale. The military got its way of supporting intruding, which would go to the heart of Japan, that is, Tokyo itself.
Enormous difficulties would rise as this thought was visibly transparent. Any invasion in Japan will result in these casualties. But the Japanese were clever as they knew that very few beaches could be used for landing.
Both the sides also knew that for a big amphibious landing, only the beaches of Kyushu and Kanto near Tokyo are capable. Keeping this in mind, the Japanese took the appropriate measures in time. Because of all this, the invasion took more time to accomplish.
The Japanese surrendered though fought bravely, but America’s ultimate nuclear attack made it much more difficult for the Japanese. Thus, it resulted in this amount of days for Operation Downfall.
Why Would Operation Downfall Have Taken So Long?
A plan was made to land first on the beaches of Kyushu, and then attacked the other targets in Japan by using Kyushu beaches as the base of their planes. Then the plan afterward was by taking support of the same aircraft for landing on the beaches of Kanto to have complete domination upon the beaches of Japan and direct fires from there. The Japanese were too early to guess this plan of Americans landing on these beaches for a massive force of amphibious troops.
They also knew the locations where they would land. They, too, had their plan of retaliation for American forces. The invasion of Kyushu’s beaches was known to be fought with dangers.
There were some pundits present in the US forces who suggested the use of chemical weapons on the defenders of the Japanese. The Geneva Convention banned their service, but none of them signed it. And as before, China was attacked by Japan with poisonous gas, so it felt suitable for the US army to use them against the Japanese.
There is a PBS program X-Day, the invasion of Japan. Upon the slow reduction of Japan through starvation the General Marshall was also worried that this would have taken too long. One more thing that would have made the matter even worse was the American public, who would have turned the war upside down against accomplishing the victory with an invasion.
Conclusion
Thus, here is all about Operation Downfall including, the Co-parts Operation Coronet and Operation Olympic. All these efforts were by the Japanese to prevent the invasion of Americans in World War 2. The Japanese went through many hardships and toils and fought bravely.
They did what they could have done most as they strictly stuck to their problem. To their hapless fate, they lost their hardship battle against the Americans as they lost and surrendered to them. The Americans became bound to drop atomic bombs on the cities of Japan to prevent World War 2 and make Japan bend on its knees and surrender to them.