Today's WSJ has an editorial titled, "Islamist Terror in Paris:  Jihadists target Western principles of free speech and religious pluralism."  It describes yesterday's slaughter, then notes:

Wednesday's massacre, following a long string of plots foiled by police in the U.K., France and elsewhere, is a reminder that jihadism isn't a distant Middle Eastern phenomenon. There will be many more such attempts at mass murder, and authorities in the U.S. and Europe need broad authority to surveil and interrogate potential plotters to stop them.

This offends some liberals and libertarians, but imagine the restrictions on liberty that would follow if radical Muslims succeed in blowing up a soccer stadium or half a city. Men willing to execute cartoonists in Paris and 132 children at point-blank range in Peshawar in the name of religion won't shrink from using more destructive means to impose mass casualties. Better to collect metadata and surveil some people now than deal with public demand for mass Muslim arrests or expulsions after a catastrophe.

Wednesday's attack also demonstrates again that violent Islam isn't a reaction to poverty or Western policies in the Middle East. It is an ideological challenge to Western civilization and principles, including a free press and religious pluralism. The murder of Charlie Hebdo cartoonists is merely the latest evil expression of a modern arc of Islamist violence against Western free speech that stretches back to Ayatollah Khomeini 's 1989 fatwa calling for the killing of novelist Salman Rushdie.