There is just too much at stake IMO, there is no way they will permit a downturn to occur in the states at this point.
By all accounts the market should have tanked big big time, given the news from Europe, the fact that it bounced I think indicates the TPTB are making sure there can be no crash allowed in the U.S.A. as we are the last straw that would break the world economies back.
The BOA announcement was timed perfectly it is a very big deal as they are only 1 of the 5 major banks starting this (there will be hundreds of thousands of loans modified by 100K or more) mostly in hard hit stated like California and Nevada.
This is big, I think they reason that once housing is stabilized and begins to bounce, The U.S.A. can take the lead and get the world economy back on track (Europe will still have a lot of work to do) but it will not be so critical once the U.S. is hitting on all cylinders.