Hamas, ISIS and Islamic fanatics

The rapid conquest of much of Syria and Northern Iraq by the fundamentalist Islamic group ISIS, and the stubborn resistance of Hamas and its sub-groups in Gaza seem almost inexplicable in this rational age. How can a group of fanatics exert such influence and achieve such military success at the expense of the well being of the people who should be their supporters and the beneficiaries of their efforts. But go back in history, look at the conquests of the Almoravids in the eleventh century, primitive but fanatical Berber warriors who conquered much of Africa north of the Sahara and the Iberian peninsula, and the Almohads who defeated them and ruled Iberia until they were defeated in 1212 by an alliance of Christian princes at the battle of Las Navas ed Tolosa and were driven back to North Africa. You might think that there is no place for such fanaticism in our enlightened age, but perhaps we are not more enlightened than the Berbers of the 11th and 12th centuries. Despite all the advances in modern science and technology our understanding of ethical behaviour, morality, and simple good judgement has not changed much over the ages.