Tighter credit conditions are a dampening factor for the US economy more generally, as lenders work to limit risk in order to repair their own balance sheets. So the real question is when the preconditions for a renewed expansion will come into place. It is perhaps a bit soon to conclude that we have reached that point.
There are certainly some helpful dynamics at work: the worst fears of a serious financial collapse have abated somewhat over the past couple of months, the process of balance sheet repair for key institutions is well under way, macroeconomic policies have been put into expansionary mode and initiatives to offer some modest support to the housing market are in train.