re: Worst Historical Disaster — Civil War or Second Great Awakening?

The Civil War is the greatest disaster to ever befall this country and likely will be until we collapse like Rome...as we inevitably will. It ripped our country in two and engendered a bitterness that, in some quarters, exists to this day.

Running a close second would be 9/11...not so much for the event itself (although that was bad enough) but for the far-reaching effects it had which will likely hasten the aforementioned collapse.