Those numbers reported ($9 trillion in guarantees) are not, repeat, are not dollars pumped into the system.

The Feds balance sheet is somewhere in the $2 trillion range (and most of that is not in the economy), with a larger intake of assets occurring in the near future as Washington gears for the stimulus package. The reason all the stimulus money is phased out over 10 years is due to the fact that the treasury cannot obtain the funds (Debt financing) unless it is spread out over several years.

There is no incentive (true incentive) that would allow investors to give that type of money to the federal government given the current rate of return on long term (not even considering short term) treasuries.