Considering Japan's traditions and view on pride, how did the allies manage to keep Japan stable after they'd been defeated? Why were there not more guerrilla warfare; Japanese people who refused to accept the defeat? Also, from what I understand, it was/is common for the winner to co-operate with the opposition in order to overturn the ruling power with whom one waged war. Was there such an opposition in Japan for the allies to co-operate with?
The important consideration here is that the average Japanese citizen recognized the completeness of their defeat. This is in part due to Hirohito's acknowledgement of it, the dropping of the atomic bombs, and the stark contrast in the physical state of the average American soldier in contrast to the average Japanese one. The defeat was total and the population largely accepted this. The decision to not prosecute Emperor Hirohito also played a major role as it allowed the Japanese to salvage some pride out of the war. Tojo became the scapegoat and the Japanese could write him off as un-Japanese based on his public statements and his attempt to commit suicide via pistol rather than a more traditional method.
There was no significant opposition to work with, and instead MacArthur made use of the Emperor to provide legitimacy to the changes that the U.S. forced on the Japanese and for the adoption of the new constitution. The decade after the war was a period of collective soul-searching for Japan that ultimately resulted in the creation of a narrative that outside elements corrupted traditional values and led the country on the wrong path. This and the failure to prosecute the emperor created the guilt-denial that still pervades Japan.
If you're interested in further reading on the subject I'd recommend John Dower's Embracing Defeat which is phenomenal.