Prominent conservatives who back John McCain as a Republican presidential candidate of principle were stunned two weeks ago when he said 60 percent of George W. Bush's tax cut would go to the richest 10 percent of Americans, but they figured it was a correctable aberration. It certainly is not, as McCain demonstrated Saturday at the Des Moines Register debate.

By chance, Gov. Bush and Sen. McCain were seated next to each other. By chance, Bush drew the straw permitting him to ask McCain a question. When he asked why the senator's tax plan takes $40 billion from working people, McCain neither defended nor explained his taxation of employer-granted benefits. Instead, he escalated class warfare another notch by looking the governor in the eye and saying: "Your tax plan has 36 percent of it going to the richest one percent in America. . . . I think that we ought to give the tax relief to the people who need it most."

That is not Republican doctrine but a windfall for Bush. While Bush's managers always feared he would be stigmatized as a moderate, McCain has enabled Bush to campaign as keeper of Ronald Reagan's supply-side legacy (once derided as "voodoo economics" by the governor's father). However timid Bush's own tax plan may be, it is surely better than McCain's.

Bush arrived in Des Moines Friday noon happy to be on the tax offensive but apprehensive about Saturday's venue. With most questions submitted by the Register's readers, Bush worried about getting bogged down in farm questions -- as reflected in his opening statement: "I hope we're able to talk about tax cuts today."

Although there turned out to be plenty of time to talk about the taxes, Bush is not comfortable going for the jugular and did not do so Saturday. The lesser Republican candidates clutter these debates, but this time Sen. Orrin Hatch was much more trenchant than Bush toward McCain: "John McCain's approach, by gosh, Al Gore and Bill Bradley, they really love it. But the Republicans don't. . . . I think we could have gotten President Clinton to give a bigger tax cut than John McCain's."

It is surely easier for McCain's adversaries to attack his tax proposal than his campaign finance reform. Apart from his inappropriate playing at class warfare, the senator has devised a plan that retains the Clinton tax increase for upper incomes, keeps the inheritance tax and contains innumerable tax hikes. McCain is no longer a conventional Republican who has defied party orthodoxy on the single issue of fund-raising. Now he has a greater apostasy.

Like the Democrats, McCain has condemned Bush for spending the entire non-Social Security surplus on tax cuts. But the size of that projected surplus suddenly has doubled, from $1 trillion over the next decade to $2 trillion, according to calculations by congressional staffers.

After the debate, I asked McCain if he would dedicate any of the extra $1 trillion to tax reduction. Not a penny, he indicated. But why? Because he views reduction of upper-bracket tax rates as a pump-primer to be used only in hard times. He mistakenly believes that Ronald Reagan cut taxes to stimulate the economy, not because the rates were too high.

"We've got a ticking time bomb out there called Social Security," McCain said at the debate, in defending his reluctance to use the surplus to cut taxes. Indeed, he is the only candidate of either party who overtly takes money raised from the federal income tax -- some $600 billion -- to finance Social Security. That step was rejected by President Franklin D. Roosevelt, who said such a transfusion of funds would turn Social Security into another dole.

It is hard to see how McCain's economic platform can be parlayed into the Republican presidential nomination. But count on John McCain's words -- about tax cuts for the rich and neglecting Social Security -- to be mined by Democrats for general election use. George W. Bush's January windfall may turn sour in November.

(C)2000, Creators Syndicate Inc.