The money stock has been expanding, just not at the rate it could potentially expand.
Also, the demand to hold money is relaxing somewhat. The result has been asset price inflation instead of broad price inflation throughout the economy. In addition to stocks, luxury housing prices have skyrocketed.
If the Fed’s official rationale is to be believed, having saved the banking system, it’s further expansion of the monetary base has the aim of pushing the unemployment rate down below 6.5 percent.