[henkster]

What, other than dropping the bombs, would have broken the psychological deadlock? Would the USSR’s entry into the war have been sufficient?

We will never know definitively, of course. But as things stand in today’s Times, that deadlock shows no sign of breaking for peace.

[colorado tanker]

I don't see how Russia's entry, by itself, would have broken the deadlock. The Japanese know we are on their doorstep and the next landing will be in the Home Islands, but they are still at loggerheads.

Had Russia taken Manchuria and Korea, wouldn't those same leaders say so what, Russia doesn't have amphibious capability so we'll just sit tight in our islands until we get the terms we want?