Nothing that Federal Reserve Bank Chairman Ben Bernanke, Treasury Secretary Timothy Geithner or President Barack Obama can do at this point is going to prevent this country from going into another Great Depression.

"No amount of government stimulus will prevent it," according to Harry S. Dent Jr. He, of course, made his reputation for forecasting with the 1993 book, The Great Boom Ahead, which came at a time when Japan was supposed to be taking over the world and instead was entering a two-decade funk.

Now, he says it's our turn. For years, he's been predicting a huge downturn that will last until 2023. His latest tome? The Great Depression Ahead.

The baby boom is what drives Dent's economic forecasting. If more people are contributing to the economy than taking out, you have prosperity and budget surpluses. Thank the babies, not Bill Clinton, for the brief period the United States had a budget surplus at the turn of the century.

Now, the economy is about to fall off the wall, he says.

"Our code word for it, a couple years from now, we think it's going to be Humpty Dumpty," Dent said.

Baby Boomers are aging and their demands on the nation's economy (in Social Security and healthcare) are about to surge, as they retire.

With the burst of the financial sector, the nation's debt in all forms stands at $102 trillion, he says. $15 trillion of federal borrowing. $17 trillion of financial debt (think: mortgage loans). $11 trillion of corporate debt. $14 trillion of consumer debt. $46 trillion of unfunded federal liabilities, in Social Security and healthcare.

This debt will have to be restructured, Dent said. But it will be the cleansing of a depression that will do it. The stimulus that the government can now throw at its problems is too little. The crack is coming. Humpty will tumble.

"All the king's horses, all the king's men could not put Humpty Dumpty back together again," he noted.

Dent's demographics are pretty compelling and you bet against them at your company's peril.

But take note of this fact: Demographically driven investing strategies don't always work out.

In 1999, as the boom roared, Dent lent his name to an AIM mutual fund that would be titled Dent Demographic Trends.

That fund lasted six years.

Subscribe Now

Access to premium content including in-depth coverage of mutual funds, hedge funds, 401(K)s, 529 plans, and more.

3-Week Free Trial

Insight and analysis into the management, marketing, operations and technology of the asset management industry.