Once upon a time, there was a fiscally and socially responsible senator named John McCain. Despite his presidential ambitions, the Republican from Arizona spoke out against the economic royalism of his party's leadership in the White House and Congress, and simply said no.

He rejected the Bush tax cuts in 2001 because they provided an unearned bonanza for America's wealthiest citizens while giving a pittance to the middle class and nothing to the working poor. To him, as a long-standing enemy of waste and profligacy, these proposals were not only unfair but also unwise.

"I cannot in good conscience support a tax cut in which so many of the benefits go to the most fortunate among us at the expense of middle-class Americans who need tax relief," he said, joining courageously with Lincoln Chafee, then a senator from Rhode Island, as one of two Republicans who dared to cast such a crucial vote against president and party.

Now Chafee is no longer in the Senate, having lost reelection in 2006 after enduring a brutal primary challenge from the Republican right. And McCain, now driven by ambition rather than principle, has changed. He supports the tax cuts that his conscience once moved him to oppose — and indeed, he promises to deliver even more lucrative benefits to those who need relief least, at the expense of those who need it most.

Tax policy is rarely regarded as a character issue. It is possible to believe that rewarding the rich should be the main purpose of the tax code, and it is also possible to believe that taxation should advance rather than diminish equality — and it is possible for honorable people to argue either way. But in McCain's case, the complete flip-flop and implausible explanation raise disturbing questions about his integrity. (That is particularly true of a candidate like McCain, who questioned the character of a primary opponent, Mitt Romney, for revamping his positions on abortion and other social issues.)

By the time McCain voted against the Bush tax cuts in 2001 and 2003, he had established a strong position against their regressive effects. That stance marked him as a true maverick in his own party and a straight talker who spoke for the national interest against his own personal interests. Running against George W. Bush in the 2000 GOP primary, he mocked the Texas governor's "misplaced" bonanza for the affluent.

"Sixty percent of the benefits from his tax cuts go to the wealthiest 10 percent of Americans — and that's not the kind of tax relief that Americans need," he said. Despite his wife's inherited wealth, he criticized proposals to repeal the estate tax for the same reason, noting that such legislation "would provide massive benefits solely to the wealthiest and highest-income taxpayers in the country."

As the chance to run for president again drew closer, however, McCain shifted toward conservative orthodoxy. In 2005, he voted for cuts in capital gains taxes that he had previously opposed, and in 2006, voted for essentially the same estate-tax repeal he had once denounced. And today, his economic platform extends to the Bush tax cuts and renders them still more regressive — and more expensive.

According to the nonpartisan Tax Policy Center, the McCain proposals would render almost one-quarter of their benefits to the top one-tenth of 1 percent of taxpayers. Those are households with annual incomes over $2.8 million. Families in the lower 60 percent of the income scale would receive 8 percent of the McCain plan's benefits. This scheme will result in the loss of at least $4 trillion in revenue over the coming decade, as our physical infrastructure crumbles.

Even more troubling than those numbers, however, is the contorted rhetoric that the Republican nominee-to-be has used to justify his policy reversal. Over the past several months, you see, he has discovered that he never really opposed the Bush tax cuts as unfair. He only opposed them because there weren't enough spending cuts to balance the revenue reductions.

At the same time, however, he now insists that cutting taxes actually increases federal revenues — the discredited supply-side mumbo-jumbo that he must endorse to win over his party base. But if reducing taxes actually raises revenues, then why is he so worried about spending cuts?

Intellectual honesty was the currency of the straight talker, yet he has squandered that great asset by pandering to the most irresponsible ideologues. How he can bear to do this to himself is a mystery.

Joe Conason writes for the New York Observer (www.observer.com). To find out more about Joe Conason, visit the Creators Syndicate website at www.creators.com.

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