"The scary part from an economic perspective is we're not going to know we've reached that point where we've borrowed so much that we're not looking like a safe investment," she said. "We're not going to know that until it happens - very rapidly. It's sort of like you don't known you're near the edge of the cliff until you're already off the cliff."

Like Greece and Italy, experts say if that happens, interest rates on U.S. securities will spike, making it costlier for the country to repay its debts. Lim Rogers says it's a burden the next generation would be forced to carry.

That's why New America Foundation's Peuquet says the supercommittee can not afford to fail.

"Extending the deadline would be much better than failure, because it keeps the conversation going," he said. "We've got the focus of the world, the markets, businesses, the American public. And this is a real opportunity, so we hope the supercommittee recognizes that."

Failure to reach a deal by November 23 would trigger automatic spending cuts worth more than one trillion dollars. Those cuts would come primarily from defense and domestic spending programs - without the benefit of new revenue.

"So it's a spending side only approach, it leaves us with a very spending heavy strategy for deficit reduction at a time when we're still struggling to come out of our recession," said Diane Lim Rogers.

Such "brute force" spending cuts could hurt social programs for unemployed and lower income Americans and hamper the country's military readiness.