Even with greed, highly paid aggressive bankers, credit-default swaps, and those geeky quants, we would almost certainly have muddled through the fallout from the bursting of the housing bubble without a full-blown financial crisis had there not been millions of mortgages made to people with chequered credit and no down-payments.
And if there's anyone out there who still doesn't believe this constitutes a full-blown crisis, I suggest speaking to one of the millions of Americans whose lives have been turned upside down because they don't know where their next paycheck is coming from.