After every attack, there is a pause while ideologues sniff the wind. If it is an Islamist easterly, the worst elements of the right know what to do. They score points with corpses, make weapons from wounds and say violence was a logical consequence of immigration and multiculturalism, policies they already opposed, and, for this is often overlooked, would have continued to oppose regardless of whether there were terrorist attacks.
Far from shocking them into fresh thinking, “shocking” violence confirms what they already knew. They are comfortable with it, as people always are comfortable with information that can be moulded to confirm their prejudices.
The worst elements on the left once exploited Islamism in an identical manner. When jihadis attacked New York, London or Paris they, too, joined what I called the “kill us, we deserve it” school of foreign policy analysis. In their case, it was not our tolerance of immigration that brought punishment. Rather, they explained away the crimes of an irrational religious totalitarianism as logical responses to western foreign policy, poverty or discrimination, which, and since you mentioned it, they already opposed.
Outside Stop the War, you hear less of that argument now. Perhaps it has finally sunk in that portraying Muslims as bombs primed to explode on western provocation was a picture that drew appreciative applause from a far right that held that Muslims could never live peacefully in the west.
Now the worst of the left pauses and sniffs the wind in the eager hope of having its beliefs confirmed, only if the violence is white racist violence blown in from the west. If it sounds as if I am drawing a moral equivalence, I don’t mean to. The worst of the right is in government in the United States and much of Europe. Its prejudices matter because they have the power to shape the world.