The most special of special, big-money interests has provided a civics lesson on the worst aspects of American democracy — and how politicians cave in to cash.

It was early last summer, when private equity firm Blackstone Group went public, that the public learned that Blackstone's CEO was paid $398 million in the prior year alone. His share of the investment company was valued at $11 billion. Yet, the public also learned that he paid a federal income tax rate of just 15 percent, because his income was classified as capital gains, rather than regular income, which is taxed at 35 percent.

A handful of prominent members of Congress made speeches expressing outrage at this tax loophole.Many people were asking why these billionaire executives were paying a lower tax rate than the secretaries who answer their phones.

The firestorm spread across Capitol Hill, with many lawmakers vowing to close the loophole.

But, something happened between that time and last fall when Senate Majority Leader Harry Reid, D-Nev., quietly explained to reporters that the Senate's schedule was just too tight to consider such a measure. And something else happened in those six months or so — lots of money started flowing out of private equity and hedge funds to political campaigns.

This relative handful of billionaire investors heading up private equity funds and hedge funds spent a few million dollars to protect their tax-favored positions. It appears to have worked.

And their generous contributions have made them powerful friends who could serve to protect their interests longer term, in case the issue resurfaces.

An Associated Press article this week noted that 40 executives in the loosely regulated investment arena of private equity funds and hedge funds have contributed to Democratic presidential candidates Hillary Clinton and Barack Obama. These executives have generally raised about $100,000 each for their favored candidates and, as a group, they've kicked in more than $6 million to these two candidates' campaigns.

Beyond the campaign trail, private equity firms have paid out an estimated $5.5 million for lobbying to make sure that their tax loophole remains.

And connections to the private equity special interests are not just financial, they are personal with the Clintons. Former first-daughter Chelsea Clinton was hired by Avenue Capital Group, a New York hedge fund. And former President Bill Clinton has a unique partnership arrangement with billionaire investor Ron Burkle through which he has earned so-far undisclosed riches serving as an adviser to Burkle's equity fund.

So, even though it appears there is a clear issue of fairness in closing this tax loophole enjoyed by a few extremely wealthy investors, politicians in Washington, D.C., have placed their own financial and political interests first in pushing this issue to a back burner.

And now that this small group of elite investors has proven to be such generous campaign contributors, it looks like they will retain their questionable tax loophole.

It's been estimated that closing the loophole would bring an additional $6 billion to the Treasury. So, since Reid, Clinton and Sen. Charles Schumer, D-N.Y. (Wall Street's other senator), have decided they don't want to close that loophole, those billions will come from other, less-wealthy taxpayers.

And this is from leading Demo-crats, the party that boasts of its allegiance to the welfare of average Americans. It seems that the realities of campaign finance and politics have now made them the party of the superwealthy Wall Street elite too.