Hillary Rodham Clinton recently jumped on Barack Obama for what her aides called "a pretty big flip-flop" as Obama began to backpedal from a pledge to participate in the federal public campaign financing program in the general election. The program would limit each presidential nominee's spending to $85 million in taxpayer-donated dollars between the August conventions and the November election. Both Clinton and Obama opted out of the public financing system during the primary campaign. Now that Obama is breaking fundraising records as he draws about $1 million a day, he apparently doesn't see private campaign cash to be as corrupting as before. Well, Obama did promise change. The funny part is that Clinton's position on public financing has evolved, too. She used to say she would not participate in public financing in the general election -- now campaign aides say she might. Not that it would matter. If history is any guide, then Team Clinton II would waste little time putting together a price list for donors interesting in buying -- er, spending -- quality time in the White House.

As for John McCain, he, too, has begun attacking Obama for backtracking on his public financing pledge. Oddly, McCain, a self-styled reformer, now hints that he'll stick with public financing -- if Obama does. "If Sen. Obama goes back on his commitment to the American people, then obviously we have to rethink our position," McCain told reporters. Someone on McCain's staff might want to tell him he is too old to cry, "He started it first."

Worse, at this very moment McCain is trying to wiggle out of the public financing system in the primary, which caps spending at $54 million. McCain signed an agreement to use public financing. But he never took the money and instead used it as collateral on an unused line of credit. Federal Election Commission Chairman David Mason sent McCain a letter last week telling McCain he can't withdraw from the public financing system. McCain's lawyers are challenging Mason.

For his part, Obama claims he will accept public financing if McCain pledges to curb independent political groups (known as 527s).That's disingenuous, too. Obama, a lawyer, must know that election law expressly prohibits McCain aides from telling 527s what to do and not do.

What a waste of hot air. After the finger-pointing and scapegoating, we all know how this is going to end. Both the Democratic and Republican nominees will opt out of public financing in the general election. The candidates can raise more than the $85 million cap, so they're gearing up to grab as much cash as they can -- then blame the other nominee for making them do it. And voters won't blame their party's nominee for choosing special interest money over public money, because winning is everything.

Besides, voters tend to resent special-interest money mainly when it flows to the other party.

Figure that, by 2012, even the pretense of public financing will be gone. A system designed to free candidates from having to go hat in hand to Fat Cats to fund presidential campaigns can't free them from a bondage they willingly assume. And the momentum is with More Money.

In 1996, gazillionaire Steve Forbes opted out of public financing in order to evade the system's strict spending limits in the primary. In 2000, Forbes and George W. Bush, a fundraising ace, sat out the primary. In 2004, Bush, John Kerry and Howard Dean said no to primary public financing funds. By 2008, Clinton and Obama opted out. In the GOP, Mitt Romney, who -- I'll throw this in just because it's an interesting item -- spent $167,000 of his own money for each of his 253 delegates, according to the Boston Globe, bypassed public financing. Ditto Rudy Giuliani. John Edwards and John McCain both signed on for public financing funds -- although apparently McCain was simply sticking a toe in the water. Other candidates -- Joe Biden, Chris Dodd, Tom Tancredo -- took public financing, which only reinforces the perception that public financing is for losers. And you know what? It doesn't matter that public financing is fading away, because there is no law that can keep Big Money out of presidential politics. When Washington passed campaign contribution limits -- the law now limits each person from giving more than $4,600 to any candidate for the primary and general election -- big donors started writing big checks to the parties. The McCain-Feingold campaign reform act limited soft money (big checks) to parties; the money flowed to 527 campaigns. You can't stop it. It's like water working its way downhill. Or aging. So when Washington passes laws to limit where big money goes, the new laws only end up making it harder for voters to know where the big money went.

Washington would do better gutting these do-gooder laws that can't deliver. But the urge to promise the public the illusion of reform runs deep.

In a 2004 interview in his Senate office, I asked McCain what it would take for him to realize that McCain-Feingold didn't block big money, but simply diverted its flow to less visible and less accountable interests.

McCain countered, "The problem is the 527s, but that's not a problem with the law. That's the problem with the Federal Election Commission." No doubt, FEC staffers now are enjoying watching McCain pushing for the FEC to cut him some slack.