sentences:  The case studies range from national security, to threatening technologies, to the global economy, to climate change and speculates on various potential threats to civilization.The authors cover seven case studies in which data driven, proven, credible experts specifically warned of a pending catastrophe, were ignored by the decision makers, and the disaster subsequently struck just as predicted.The authors call these seers, "Cassandras" after the Greek mythological figure who could foretell disaster but was cursed to never be believed.