Basically, everyone has always said that everything is on the verge of collapse. I think it's near-sighted, historically, to say that we're "Destined for complete annihilation unless we..." because everyone has been saying that at every point (bar a few) throughout history.
I think you are understating it.
Until the past 10 - 15 years, we have NEVER had a global economy. Sure, with the depression, the various economies were a little shaky, but they were off through inner reasons as well.
Also, we have never accumulated as much debt as we have right now (which is roughly our GDP) nor have we created an economy that relies heavily on credit.
With all these factors in mind, we are looking at a very scary house of cards. If we had defaulted a few weeks back, the companies that we owe money to would lose their debt as well as the interest we were paying on them. If, for the sake of concreteness, we borrowed $100, but we can't pay it back. But, have an interest on it at 7%, which is all we can really afford, so we pay $7 a year. They then rely on that money to fund their government programs.
This is how we work now.
EDIT: This is not me saying "WE ARE ALL GONNA DIE!!!" This is me acknowledging the system that we rely on and erroneously build up is faulty and not stable/permanent.
Whoever leads us, should really consider this a priority concern.