David Harvey gives a Marxist view on "why the stimulus package is bound to fail":
In the United States, any attempt to find an adequate Keynesian solution has been doomed at the start by a number of economic and political barriers that are almost impossible to overcome. A Keynesian solution would require massive and prolonged deficit financing if it were to succeed. It has been correctly argued that Roosevelt's attempt to return to a balanced budget in 1937-8 plunged the United States back into depression and that it was, therefore, World War II that saved the situation and not Roosevelt's too timid approach to deficit financing in the New Deal. So even if the institutional reforms as well as the push towards a more egalitarian policy did lay the foundations for the Post World War II recovery, the New Deal in itself actually failed to resolve the crisis in the United States.(Hat tip DP for Harvey)
The problem for the United States in 2008-9 is that it starts from a position of chronic indebtedness to the rest of the world (it has been borrowing at the rate of more than $2 billion a day over the last ten years or more) and this poses an economic limitation upon the size of the extra deficit that can now be incurred. (This was not a serious problem for Roosevelt who began with a roughly balanced budget). There is also a geo-political limitation since the funding of any extra deficit is contingent upon the willingness of other powers (principally from East Asia and the Gulf States) to lend. On both counts, the economic stimulus available to the United States will almost certainly be neither large enough nor sustained enough to be up to the task of reflating the economy.
P.S. 13 Feb: Paul Krugman writes:
The Congressional Budget Office, not usually given to hyperbole, predicts that over the next three years there will be a $2.9 trillion gap between what the economy could produce and what it will actually produce. And $800 billion, while it sounds like a lot of money, isn’t nearly enough to bridge that chasm.