I liked Don and Cathy's answers - it isn't any of Obama's doing. His was wringing his hands over forcing everyone to buy health insurance while the housing industry was wallowing in the mire created by Bernanke after greed overtook common sense.
Greed in California infected Nevada and quickly spread to many places, primarily Blue States (with the notable exception of D/FW and the other Red States. Yes, Red States have suffered some as the economy plummeted into recession after Bernanke choked off the speculation with exorbitant interest rates that collapsed ARMs and option ARMs. The Wall Street speculation in junk mortgage portfolios based on these loans made by greedy GSEs, like FHLMC and FNMA, eventually collapsed and took down Iceland and several overseas government bettors, too.
Backtracking immediately might have propped up the mess long enough to stabilize, but Bernanke has his foot on the throat of the housing speculation monster (and he killed it). Unfortunately, the victims in the belly of the beast died along with it.
So, did Obama do anything to fix this? No. He told us during his campaign that his mother was cheated by insurance companies and denied coverage. His answer was to force us all to go to those same insurance companies and pay them our money, too. He fiddled while southern California "burned" and McCarron was dead. Did he help D/FW? No, but it is improving.
Should he have done anything? I prefer to remember "It's the economy, stupid"