It seems that the right decision was made to keep him; consider the industrial and peaceful country that Japan is today! Quite possibly, but no matter who occupied the throne, they would still have been subservient to MacArthur and the US's wishes. The occupation of Japan didn't end until 1952, and US forces were there in strength for quite awhile in the region. That kept them in check for a long time. The Japanese Self-Defence Force was not able to defend itself from the Soviets or anyone else, so they stayed safe and sound under our nuclear umbrella while building themselves into the self-proclaimed WW2 1st A-Bomb victimized anti-nuclear peace loving economic giant and history deniers that they are today. Their emperor is a figurehead anyway, at least as defined by their post WW2 costitution. Godzilla could be on the throne for all that matters.