And it could result in a depression so severe that he doesn't "think our civilization could survive it."
And Duncan is not alone in warning that the U.S. economy may go into a "death spiral."
Since the recession, noted economists including Laurence Kotlikoff, a former member of President Reagan's Council of Economic Advisers, have come to similar conclusions.
Kotlikoff estimates the true fiscal gap is $211 trillion when unfunded entitlements like Social Security and Medicare are included.
However, while the debt crisis numbers are well known to most Americans, the economy hasn't suffered a major correction for almost 4 years.
So the questions remain: Is the threat of collapse for real? And if so, when?
A team of scientists, economists, and geopolitical analysts believes they have proof that the threat is indeed real - and the danger imminent.
One member of this team, Chris Martenson, a pathologist and former VP of a Fortune 300 company, explains their findings:
"We found an identical pattern in our debt, total credit market, and money supply that guarantees they're going to fail. This pattern is nearly the same as in any pyramid scheme, one that escalates exponentially fast before it collapses. Governments around the globe are chiefly responsible.
Click here to see how banks are escalating the collapse..."And what's really disturbing about these findings is that the pattern isn't limited to our economy. We found the same catastrophic pattern in our energy, food, and water systems as well."
According to Martenson: "These systems could all implode at the same time. Food, water, energy, money. Everything."
Another member of this team, Keith Fitz-Gerald, the president of The Fitz-Gerald Group, went on to explain their discoveries.