Mock trial against the Supreme Allied Commander in the Pacific General MacArthur and his involvement in dropping the bombs.
MacArthur did not have anything to do with the atom-bombings. He wasn't even informed of the plan until a very few days before the attack. He was not considered to be in the class of people referred to in the military as "being in the need to know." In part he was not informed because there was no assurance that the bomb would even work before its first test firing in New Mexico so MacArthur needed to continue his coordination of a planned invasion of Japan scheduled for the summer of 1946.
When Harry Truman was Roosevelt's Vice-President, he wasn't even "in the need to know."
As far as the far more deadly fire-bombings of Tokyo is concerned, he wasn't even responsible for that planning either, as it was an Army Air Force operation I believe under the command of General Curtis LeMay.
One way or another, MacArthur had nothing to do with the atom-bombings.
I could look at this topic, historically, as being equal to charging me with the Oklahoma City Bombing. I wasn't there, had no conversations with the bombers, didn't even know the bombers, hadn't heard of them, and had no part in the decision. So while a mock trial is an interesting historical exercise, I can't see a way where MacArthur could ever be charged with this crime. Truman perhaps could be. It was his decision.
By following pohnpei's link above, you'll notice that by his own admission, MacArthur was not consulted about the decision, nor did he think it was the right one. So it would be a very difficult case to prosecute, with no signed orders, conversations or physical evidence that he ordered the bombing, because he didn't. It would be a very easy case to defend because, ladies and gentlemen of the jury, my client wasn't there.
This is fairly fascinating in terms of topic. I would question MacArthur as to how successful the island hopping campaign was. If this was progressing well, would Japan had not been defeated through conventional means? Why drop the bomb if victory was almost inevitable? I think that being able to ask MacArthur what his exact role was in the approval of dropping the bomb will reveal a couple of things. If he knew of it all the way through, then the question in my mind is why continue with the ground campaign? Why not simply pull troops out and let the atomic bomb do its job? If he was not in full knowledge of the dropping of the bomb, then it reflects the lowly nature of the soldier, who is the fighting grunt in the face of policy makers. In this light, I would get MacArthur to admit that his function is that of "errand boy" and this would certainly evoke a passionate stance of a lifetime soldier as MacArthur.
I assume that we are talking about the atomic bombs here. If that is the case, I do not think that MacArthur could really have stopped it. In fact, I am not convinced that MacArthur knew was even asked if he agreed with the idea of dropping the bombs.
I think that you would have a much stronger case for trying MacArthur on war crimes for the conventional bombing of Japan. MacArthur had much more control over that bombing. You can argue that the conventional bombing was just as much of a war crime as the atomic bomb.