Would blockade and bombing alone defeat Japan?

Without nuclear weapons, could the Allies blockade and bomb Japan into submission?

Not on a politically acceptable timetable; blockade and bombing could continue, but a land invasion would likely still be required.

The answer turns on time and political endurance rather than denying that blockade and bombing could damage Japan. Those operations could continue to tighten the pressure, but in this assessment they offered no quick or certain end to the war. Allied governments and publics would have to accept an open-ended campaign while Japan remained unconquered. A land invasion would therefore remain part of the plan in a world without nuclear weapons. The timetable is the decisive constraint, and the short exchange does not predict the precise point at which blockade alone might compel surrender.