By lending the banks money at zero interest rates, the FT’s Martin Wolf says, the Fed is helping the banks recapitalize themselves. The banks aren’t lending because they’re still trying to recover from all the lousy loans they made three years ago (and because there aren’t all that many folks to lend to). So there’s nothing else to do with the money other than hoard it, buy safe Treasuries, and pay huge bonuses.
It’s annoying to watch banks that would have collapsed a year ago now minting money at taxpayer expense. But that’s the way monetary stimulus always works.