The Fed's Balance Sheet: Size and Composition

Here's an illustration of the Fed's balance sheet from the Cleveland Fed.

A lot of talk has focused on the expansion of the Fed's balance sheet since Sept 2008. The big question: why no inflation? Bob Higgs writes:

Ordinarily, one would have expected this development to produce hyperinflation of the general price level. However, the price level has increased quite moderately, and for a while many analysts warned that deflation was the greater risk. [...] Not only has hyperinflation failed to appear; even garden-variety inflation of prices in general has been extremely low by the standard of recent decades.
[...]
The most obvious answer, of course, is that the banks are simply sitting on the reserves, rather than lending them to customers. And why are they doing so? The usual answer is that since late 2008, the Fed has paid the banks a rate of interest on their reserves at the Fed. This interest rate has recently been in the range 0-0.25 percent. Although this is not nothing, it verges very closely on nothing. And if one notes that the purchasing power of money has fallen at least a bit, it is clear that the banks are realizing a negative real rate of return on their holdings of excess reserves at the Fed.
[...]
Moreover, they are doing so notwithstanding that they appear to have the option of lending at 3.25 percent to their best corporate customers and at higher rates to their less creditworthy customers.

So we haven't seen much inflation yet. But if (when?) banks start lending out reserves, we should see it pick up. Right?

Good question. The standard view is that the Fed can simply sell its assets to keep the money supply from expanding when the money multiplyer picks up. But the Fed's balance sheet ain't what it used to be. It is not only larger, but also differs in terms of composition. Note that traditional security holdings have actually fallen since Dec 2007. The net increase stems from loans to financial institutions in 2008 and 2009 (much of which has already been repaid) and then large scale asset purchase programs associated w/ Freddie and Fannie starting around Jan 2009. The Fed can certainly sell these assets. But at what price? Will they be able to suck up enough money when the time comes? We will soon find out.

Addendum: Check out this Barron's article by Walker Todd and Bill Ford.