Not all Germans believed in genocide. All Nazis did
Not all people living in countries where Islam is the majority religion believe in the duty to kill to promote Islam. All PRACTICING, DEVOUT Muslims do. There's a difference between country-of-origin and ideology. Islam is an ideology
The way we dealt with National Socialism was to conquer and occupy the territory of the believers, and impose strict laws that no positive mention of Naziism was ever to be made, nor would children's indoctrination in Nazi ideology be tolerated. That instead the children of the Nazis were to be taught that Naziism was fundamentally evil. After a generation or two of occupation, Naziism as a threat was eradicated.
IMHO, this is the key in the long run. On the positive side, such things as opening up schools in Afghanistan, e.g., is a step in the right direction. What I don't see are efforts to shut down hate-preachers & their mosques en masse. I realize it's a delicate balance regarding free speech, but I don't think we even have the personnel available and working (such as translators or moles) to be listening in to see who's who & what's what. Or do we?