It's just as likely the moral hazards of yesterday were never properly dealth with, market corrections didn't properly happen during the downturn, and we're seeing a continuation of misplaced capital. ie, far too much going into residential real estate and student loans, not enough being invested in business. I remember reading that small/medium business growth and capitalization has flatlined as the housing market flourished.

In Canada where we have a similar housing crisis nearing a peak SMB growth actually declined recently.

The thing people often forget with these 'bubbles' is that it's not just risky because people lose money in their investments, but it's a massive misallocation of capital away from productive assets. Productive things like job growth and developing new industries and expanding old ones, to increase job growth and wages... which the US desperately needs, as the whole NAFTA/globalization debate highlighted.