The official declaration of surrender by the Japanese government went a long way toward removing such resistance. Moreover, you have to appreciate the context at the end of WWII. Japan was in dire straits. Most people don't appreciate that the annihilation of Hiroshima and Nagasaki was absolutely not exceptional in terms of the level of destruction, it was exceptional merely in the degree of efficiency involved. The allied strategic bombing campaign had already reached a level of capability where they could completely wipe an entire major city off the map at a rate of once per week, and had been doing so. The conventional bombing of Tokyo took more lives and destroyed more property than either of the nuclear attacks, however it required hundreds of bombers, tens of thousands of men, and a vast supply chain stretching across the entire Pacific. Meanwhile, interdiction of Japanese shipping and disruption of Japanese industry and trade had reached a point in 1945 where Japan was literally being starved to death.

Everyone in Japan was familiar with this context because they lived it. They lived through the air raids. They lived in towns that had been bombed. They had relatives or friends who had died in the war. They lived with the hunger. They experienced the full brunt of the destruction and deprivation. After the military government collapsed at the end of WWII there was a period of semi-lawlessness and desperation due to continued lack of food. The new government and allied occupation helped rectify both situations. Filling people's bellies and making the streets safer. And that kind of thing goes a hell of a long way to discourage insurrection. The vast majority of Japanese citizens in the 1940s and '50s knew exactly what war was like and were thoroughly incentivized to avoid returning to those conditions. As the Japanese economy recovered and then began to boom in the post-war years that sentiment solidified.

There's a lot more that could be said about the complexities of Japanese post-war politics, but in terms of the lack of an active insurgency, I think the above is a sufficient explanation.