It was to create the impression there was an indefinite supply of bombs, but to who? I believe there is an opinion of some that part of the motivation was to p

It was to create the impression there was an indefinite supply of bombs, but to who? I believe there is an opinion of some that part of the motivation was to prevent the Soviet Union from moving in after Japan's defeat, like they did in Europe. This is often asserted as if it were a shocking revelation and a moral indictment of the decision. However, it seems to me both a plausible motivation (I haven't bothered to read up on the evidence or don't remember if I have) and potentially morally defensible, particularly in hindsight.