Why does the Fed have to take a loss? Maybe on a MTM basis but why can't they just hold to maturity?Oh no, you've followed me....am I that interesting to you?
The Fed doesn't have to sell anything. It can just take a loss. Just like the ECB will do.
ADD: Obviously, if housing blows up again, the Fed would take a loss on any paper in which there are defaults with respect to RMBS they have purchased that is not Fannie, Freddie or GNMA.