The loose money caused the run up of real estate prices. I watched the market in California go up as much as 200% from 2002-2006.
But it was the gross over-leveraging of the big banks to buy bundled, but individually nearly worthless mortgages, that almost brought the whole system down. The over-leveraging turned what would have been an indeed disastrous misuse of capital into an overwhelming event.
The combination of fantasy seeking Egalitarian/collectivists, hoping to redistribute wealth, with foolish Republicans, putting special interests ahead of reasonable behavior, is a very bad combination. I have no use for either group--none whatsoever.