We may think there is willpower involved but more likely... change is due to want power. Wanting the new addiction more than the old one. Wanting the new me in preference to the person I am now.
We should invade their countries kill their leaders and convert them to Christianity. We weren't punctilious about locating and punishing only Hitler and his top officers. We carpet-bombed German cities we killed civilians. That's war. And this is war.