Originally Answered: Need your opinion-Were the atomic bomb attacks on Japan (Hiroshima & Nagasaki) really necessary to end the war?
Not necessary, but it actually did.
There was no choice for Japan but to surrender during 1945, even if the US did not drop the A bombs. We could not continue the war any longer.
Most of the labor force was conscripted so that there were not enough people to crop rice in autumn. The sufficient amount of grain crop was expected in Manchuria and Korea (it was an overseas territory of Japan then), however, Japan already lost the naval supremacy of the sea surrounding the archipelago so that we could not import it.
We did not have enough oil to fly a fighter plane. Nor we could manufacture weapons, because the factories were destroyed with air raids.
Surrender was already on the agenda among the Japanese leaders in June, however, they did not stop the war on the spot, because they thought that they needed a win in a battle in order to take advantage in the negotiation. They considered that they had to protect the monarchy by any means.
Your commanders must have known the fact. General Marshall, General Eisenhower, and General MacArthur opposed the A-bombing to the Japanese cities, I have heard.
Nevertheless, it was also the fact that our Emperor determined the surrender, partly because of the A bombing. When Japan accepted the Potsdam Declaration, he addressed to the Japanese nationals as below:
He then cites, "Moreover, the enemy has begun to employ a new and most cruel bomb, the power of which to do damage is, indeed, incalculable, taking the toll of many innocent lives"); ... the remark is interpreted to refer to the atomic bombings of Hiroshima and Nagasaki that occurred days before the speech. ... Finally, and most famously, he says: "However, it is according to the dictates of time and fate that We have resolved to pave the way for a grand peace for all the generations to come by enduring the unendurable and suffering what is unsufferable." (Wikipedia)