(By Keith Fitz-Gerald) Everything we know about classic economic theory suggests the U.S. economy should be experiencing Zimbabwe-like hyperinflation right now, thanks to the nearly $2.2 trillion the U.S. Federal Reserve has pumped into the system.

But we're not…yet.

Classic economic theory says that money supply can be used to stimulate the economy and our central bankers seem to agree. That's why they've pumped more than $1 trillion dollars into the economy, engineered countless bailout bonanzas for zombie institutions, put Detroit on life support, and delivered a bunch of financial Band-Aids to the trauma ward – all in a desperate bid to make Americans feel better about the global financial crisis.

To their way of thinking, the trillions of dollars have been a success. That's why any meeting of the Group of Eight (G8) nations looks more like a mutual affection society with central bankers anxious to claim credit and backslap each other in congratulations for having avoided the "Great Depression II."

But by taking the Federal balance sheet to more than $2 trillion from $928 billion 2008, they've created a situation that should have resulted in an epic inflationary spike to accompany the 137% increase in liabilities.

Yet that hasn't quite happened.

Core inflation – which denotes consumer prices without food and energy costs – has actually decreased from 2.5% in 2008 to 1.5% presently. And that has many investors who have heard the siren call of the doom, gloom and boom crowd wondering if they're worried about nothing.

So what gives?

Well, there are four reasons we haven't yet seen hyperinflation:

• Banks are hoarding cash. Despite having received trillions of dollars in taxpayer funded bailouts and lived through a litany of shotgun weddings designed to reinvigorate the shattered lending markets, most banks are actually hoarding cash. So instead of lending money to consumers and businesses like they're supposed to, banks have used taxpayer dollars to boost their reserves by nearly 20-fold according to the Federal Reserve. The money the bailout was supposed to make available to the system is actually not passing "Go," but rather getting stopped by the very institutions that are supposed to be lending it out.