All I am saying is that is it possible that this paranoia that you seem to feel (if I'm wrong I'm not meaning to offend) is simply due to the news that we are exposed to everyday? War, Bad Economy, Corruption, etc.
Members of every generation since the beginning of time have thought they were the last to inhabit this Earth b/c the world would end before anyone else could. It's not uncommon to see people fearing the downfall of civilization when all they are fed throughout the day is bad news.
I'm not saying that it's impossible to have people predicting the dissolving of the US during the times of prosperity, but I do think it's much more likely that these conversations sprout due to the fact that people do not understand the changing world around them OR they are disillusioned by the news that they hear.
I'm not meaning to call anyone out or anything like that, but I am considering that people turn to what they know best in times of "chaos" and assume the worst and that is the US which has stood as a superpower and a global economic force to be reckoned with and assume that it will follow the same path that other nations had followed.
Throughout however many recessions we have had...people predict doom for this country. This is no different. Recession = stress = radical ideas and predictions.
If I die today, I'm happy how my life turned out