If history is any guide (especially recent history), government intervention occurs after the crisis rather than before.
A lot of the government support is scheduled to end over the short term (1-2 years). I think they will wait until the housing market starts dropping again, Then they will be totally free to enacting another emergency measure that modestly helps to re-stabilize the housing market while, coincidentally, making a few well connected people and corporations very wealthy in the process.
Its just a lot easier to do this during a crises rather than beforehand.
