Ever since the financial crisis struck, and the Federal Reserve began “printing money” in an attempt to contain the damage, there have been dire warnings about inflation — and not just from the Ron Paul/Glenn Beck types.

Thus, in 2009, the influential conservative monetary economist Allan Meltzer warned that we would soon become “inflation nation.” In 2010, the Paris-based Organization for Economic Cooperation and Development urged the Fed to raise interest rates to head off inflation risks (even though its own models showed no such risk). In 2011, Representative Paul Ryan, then the newly installed chairman of the House Budget Committee, raked Ben Bernanke, the Fed chairman, over the coals, warning of looming inflation and intoning solemnly that it was a terrible thing to “debase” the dollar.

And now, sure enough, the Fed really is worried about inflation. You see, it’s getting too low.

Before I get to the trouble with low inflation, however, let’s talk about what we should have learned so far.

It’s not hard to see where inflation fears were coming from. In its efforts to prop up the economy, the Fed has bought more than $2 trillion of stuff — private debts, housing agency debts, government bonds. It has paid for these purchases by crediting funds to the reserves of private banks, which isn’t exactly printing money, but is close enough for government work. Here comes hyperinflation!