Okay, let's all agree: Nobody likes to pay taxes. That's why the major candidates for president and many other politicians standing for election this year favor tax cuts or something they call tax reform.

There are plenty of reasons to make such changes that go beyond a visceral distaste for sending money to Washington. By general consensus, the federal income tax is too complicated, too easily gamed and therefore unevenly burdensome to people and companies that have the same incomes. In other words, it's unfair.

President Bush, who has referred to the tax code as "a complicated mess," is said by aides to support a flat or at least a flatter income-tax structure. Sen. John F. Kerry (Mass.), the Democratic presidential nominee, wants to lower taxes on both the middle class and U.S. corporate income while closing loopholes that shelter company earnings overseas. And there are lots of other proposals floating around as well.

Yet some things prevent taxes from being altered in truly serious ways. The first and more important is revenue. Any large alteration in taxation would almost inevitably cost a lot of money.

Then there's the impact on different individuals and firms: Some would benefit by paying less while others would have to pay more to compensate. No matter what kind it is, tax reform will create both winners and losers. An internal Treasury Department study conducted in 2002 warned that any significant simplification of the nation's tax system would probably lower taxes for wealthy people and increase them for others.

That kind of trade-off can be tolerated only if there's cause enough to make so big a change. So far, however, that's another essential element that's been missing from the public debate. Sure, the tax code's unfair. But that's old news. Why go through the pain of revamping the income tax if there isn't an overwhelming and compelling reason to do so?

Well, last week Citizens for Tax Justice and the Institute on Taxation and Economic Policy tried to make the case that the time has finally come. The groups reported that 82 of America's largest and most profitable companies paid no federal income tax in at least one year from 2001 through 2003. Twenty-eight corporations had negative income tax rates over the period.

Back in the 1980s, a similar finding by the labor-backed Citizens for Tax Justice helped instigate the most sweeping rewrite of the income tax in history, the Tax Reform Act of 1986. And this time, Democrats were trying to draw comparisons with that period. But until the average person actually feels the inequity -- and budget deficits subside, freeing up extra revenue -- experts don't expect to see big-time tax overhaul no matter what the politicians say.

-- J.H.B.