The cases of Germany and Japan were quite different...

In the case of Japan, we allowed Emperor Hirohito to stay in power, and he instructed the population not to resist, and he played along with the occupation. If he had been removed from power in favor of a new US puppet government, things would have been quite different.

In Germany (West Germany), while many the top Nazi leaders were tried for war crimes, the new government consisted of mostly former Nazi politicians. Local politicians were allowed to stay in power as well. In addition, the German public were forced to see the remains of the death camps. Most of them were quite shocked and ashamed, although it was quite a common viewpoint of Germans in 1945 that the death camps were a hoax created by the Russian communists to make the Nazis look bad. But I'm sure reality eventually sunk in.

These cases are quite different than just simply launching an attack on a country and then occupying it like we did in Iraq, or like we did in Vietnam in the 1960s. Wars like that simply cannot be won. The rebels will continue to fight on for as long as we stay. The war will end when we decide we have had enough and decide to go home.