Amid the pious thinking about lessons learned after the great financial crisis five years ago, it's worth returning to the fork in the road, when Wall Street's fortunes began to separate from Main Street's prospects.
Beginning in the 1980s, investment banks got into the business of trading for their own accounts. "The ethical problems came when proprietary trading began to overshadow customer services," Michael Santoro, professor of business ethics at Rutgers University, wrote in his book, "Wall Street Values."
Greedy Wall Street behavior—as captured by Michael Douglas's Gordon Gekko in "Wall Street"—benefited the rest of us, to a certain extent. "When you're serving clients, greed can work," Santoro said. "If your profit is based on the prosperity of the client, what's good for your client is good for society."
But in the new financial world order, Wall Street greed is about just that—Wall Street's interests. "The problem on Wall Street today is greed is no longer working for everyone else because the interest of Wall Street is separated from the interest of the rest of society," Santoro said.
Some ethics experts and Wall Street watchers argue that the seeds of another catastrophic meltdown or massive taxpayer-funded bailout don't lie in bank capital requirements or regulations. It's about ethics. Values.
"At great cost, we learned that greed, unless tempered by good values, does not 'work' from a social perspective," according to Santoro.
(Read more: Timeline of the financial crisis, back from the brink)

