Mortgage Confidential: Who is culpable for the credit crisis?

I got this email today (a good one) from a reader wanting to know who we should hold responsible for the mortgage "crisis."

Q: David: Can we hold our political leaders responsible for the financial crisis comprising misrepresented mortgage-based financial vehicles, like CDOs, derivatives, and other mortgage portfolio "packages" or is this so-called crisis just the by-product of a "natural" inclination of the mortgage market to correct itself in accord with principles of supply and demand? In other words, is there a specific group of humans culpable for this crisis?

A: Good question. Here's my answer.