THE only time art ever seems to make news here in the West anymore is when a Pollock or Warhol sells for a sum commensurate with the budget of a “Transformers” film. It seems bizarre, then, to find ourselves grappling with international crises in which art is the issue: the imbroglio involving the Sony movie “The Interview,” the massacre at Charlie Hebdo in Paris. The incomprehension, whether bemused or horrified, that we feel toward people who take up arms against the creators of cartoons or comedies is a chastening reminder that there are still cultures in which art is not a harmless diversion or commodity, but something real and volatile, a potential threat to be violently suppressed. These attacks are, in a way, a savage, atavistic show of respect.