However, it is known that the predicted number of U.S. combat deaths in the planned invasion escalated enormously among pro-bomb commentators from the U.S. War Department's 1945 prediction of 46,000 dead.
(snip)
This “deeply flawed” analysis by Giangreco is the very article upon which Kamm’s repeated assertion of projected high casualties relies so heavily.
Careful historians do not deny that Truman was concerned at the prospect of many U.S. lives being lost in an invasion of Japan, but the predicted numbers were far less than the inflated figures provided postwar to ‘justify’ the atomic bombings. Such figures, along with Japan’s “rejection” of the Potsdam Proclamation, form part of the conventional narrative that the atomic bombs were sadly necessary. But as Hasegawa observes astutely:
Evidence makes clear that there were alternatives to the use of the bomb, alternatives that the Truman administration for reasons of its own declined to pursue. And it is here, in the evidence of roads not taken, that the question of moral responsibility comes to the fore. Until his death, Truman continually came back to this question and repeatedly justified his decision, inventing a fiction that he himself came to believe. That he spoke so often to justify his actions shows how much his decision to use the bomb haunted him.”[31]
Media Lens - Racing Towards The Abyss: The U.S. Atomic Bombing of Japan
Again, reading the same information, two different conclusions are reached. However, let's turn this a bit, might be lost is an unknown. Dropping the bomb is a definite. And it wasn't soldiers fighting a battle, but civilian lives being taken, and terrorizing the government and the people. Not amount of war causalities can justify such wanton death and destruction. Not morally. There's no Christian teaching that allows it.