Hi clo,
I don't think the US currency is going to collapse. That is something which would come with hyperinflation. No sign of that, in spite of years of arguments from the Paulista right.
If people wish to barter, let them do so. But I'm seeing a robust dollar which fulfills its function as a medium of exchange (in a variety of forms) and as a long run store of value (see 10 year bond rates).
I think debt holders and savers are going to take something of a hair cut. But this will occur over a number of years and due to the action of inflation over time. So I'm all for loose monetary policy, QE etc. These are designed to get the economy moving again. They will do so at the expense of some portion of the value of the money that already exists. The overhang of folks protecting their savings is the big obstruction in the way of the recovery. What we need right now is more investment and consumption.
Who is going to initiate these two things if not the government?
Far from being upset that money values reduce over time, I see it as a relief.