This is why I don't jump on the "America is doomed" bandwagon: history has a way of radically turning on the seemingly smallest of things---the Archduke decides abruptly to visit his wounded guard and changes his route into Gavrilo Princeps' path; Joshua Chamberlain orders a contrary-to-the-book bayonet charge at Little Round Top; a Japanese scout plane flies right over US carriers at Midway in broad daylight and doesn't see them; the Jamestown settlers, out of supplies, literally meet a supply ship at the mouth of the James River; a hurricane hits New Jersey just as Obama is on the ropes.
I could go on and on but the point is, events with unexpected importance are occurring all the time and are beyond the ability of people to predict.