Catastrophic

From A History of the World in 10 1/2 Chapters by Julian Barnes:

How do you turn catastrophe into art?

Nowadays the process is automatic. A nuclear plant explodes? We'll have a play on the London stage within a year. A President is assassinated? You can have the book or the film or the filmed book or the booked film. War? Send in the novelists. A series of gruesome murders? Listen for the tramp of the poets. We have to understand it, of course, this catastrophe; to understand it, we have to imagine it, so we need the imaginative arts. But we also need to justify and forgive it, this catastrophe, however minimally. Why did it happen, this mad act of nature, this crazed human moment? Well, at least it produced art. Perhaps, in the end, that's what catastrophe is for.

This would make more sense if that final line said "that's what art is for," but I'm not sure exactly why. I'd rather try to answer the question "What is art for?" than "What is catastrophe for?" And even then it would depend on whether we're talking about man-made catastrophes (murders, terrorist acts) or natural catastrophes. "What is an earthquake for" raises questions about the existence of God and the problem of pain, but "What is mass murder for?" seems a ridiculous question, suggesting that terrorism fulfills some natural purpose on the planet; how could both questions possibly have identical answers? I'm scratching my head over this one.