Videos currently reaching me are unbearable. I have no means of knowing if scenes in Syria and Iraq of Gestapo-style mass executions, beheadings and crucifixion really took place, or are faked to frighten everyone. However, tens of thousands of Christians and Yazidis are fleeing from the so-called Islamic State on the only possible route across inhospitable mountains. An Iraqi general is on the record saying that 70 percent of these unfortunates have already died. President Obama and Prime Minister David Cameron are convinced that the plight of these refugees is real enough to fly in “humanitarian aid,” that sticking plaster for the liberal conscience, but not frightening enough for them to send in troops or to suspend their own carefree summer vacations.

Writing in Latin shortly before the birth of Jesus Christ, Lucretius is remembered for a hard-hitting line which I shall render as, “who would have thought that religion is capable of such evil acts.” Islamists everywhere are engaged in a war of religion, that most savage of wars. Those waging it are too self-righteous to compromise, and in the name of their religion they rejoice in the evil of suppressing, expelling, or murdering each and every minority in their midst.

Islamist Hamas is a model of uncompromising self-righteousness. For that reason, many throughout Europe support Hamas in its war to eject the Jewish minority from their midst. For reasons that must go deep into Europe’s history, this reaction serves the deluded purpose of landing responsibility for Hamas’s evil acts on to Israel. But the choice facing Israel is either to be another minority running away for dear life like Christians and Yazidis, or to take up arms and defend themselves. There are no two ways about it.