“Unacceptable.” “Offensive.” “Disgusting.”

Those are some of the words US officials of both parties have used in the past to describe Charlie Hebdo and others that have taken aim at Muslims and their prophet over the past decade.

After Wednesday's deadly attack on the French satirical weekly, the slain French cartoonists have been eulogized as “martyrs for liberty” on both sides of the Atlantic. But the sudden change of tone masks a deeper ambivalence in both Europe and the United States over the proper role of Western governments in standing up for freedom of expression when it takes aim at religion — in particular Islam, which forbids representations of Muhammad.

“Free expression and a free press are core values; they are universal values, principles that can be attacked but never eradicated, because brave and decent people around the world will never give in to the intimidation and the terror that those seeking to destroy those values employ,” Secretary of State John Kerry vowed in a statement Wednesday. “I agree with the French imam [Hassen Chalghoumi of Drancy], who today called the slain journalists 'martyrs for liberty.' Today’s murders are part of a larger confrontation, not between civilizations — no — but between civilization itself and those who are opposed to a civilized world.”