Leave them to ressurect their caliphate. You have to let them burn themselves out and see if islamism is a sustainable way to organize a society. If so, they will build up and probably industrialize and from hich class struggle will become a thing, and an educated population will hate the government and try to overthrow it
if it isn't, their ideology will be discredited and other ideas can creep back in
bombing them and oppressing them in other ays just makes them more popular