hypervolcano

— 2007 August 2, History Doomed To Repeat, at www.unexplained-mysteries.com Yes, there is always the uncertainty of some natural disaster overwhelming the US and precipitating a collapse. The eruption of the hypervolcano under Yellowstone could be such an event, or the collapse of the volcanic cone (forget it's [sic] name) in the Canary Islands sending a tsunami to devastate the east coast. However these are unpredictable and I don't consider such events as repetitions of some unalterable historical cycle of the rising and falling of civilisations.