For a brief 48 hours, it looked as if John McCain was courageous enough to say something sensible about tax policy—and as a result was immediately attacked by both the right and the left.

Today’s Wall Street Journal reported disapprovingly that McCain would consider payroll taxes as a way to bolster Social Security’s finances.“Mr. Stephanopoulos [on ABC’s This Week] pressed, ‘So that means payroll tax increases are on the table, as well?’ Here came the words that have caused the McCain campaign well deserved grief: ‘There is nothing that's off the table. I have my positions, and I'll articulate them. But nothing's off the table.’”

The Journal also reported that the Democrats were preparing attack ads accusing McCain of flip-flopping and hypocrisy on taxes since he’d earlier vowed to never raise taxes and had criticized Senator Obama for saying he would.

This was a good flip-flop, though—like Obama’s grudging acceptance that the surge in Iraq, which he’d initially opposed, seems to be working.We should cheer when candidates recognize reality, however late in the game. I don’t know if higher payroll taxes should be part of the solution to Social Security’s long-term ills, but why rule them out before negotiations even begin?It is simple arithmetic that any sensible solution requires cuts in benefits, higher taxes, or some combination of the two.Ruling out options 2 and 3 would wreck any reform effort.

More fundamentally, the enormous demands placed on government by the retirement of baby boomers and rising health care costs will, at some point, require additional revenues.Slowing the growth of spending, especially for the big entitlement programs—Social Security, Medicare, and Medicaid—is necessary too, but almost nobody believes that will be the whole solution.

But, alas, today it was back to read my lips: “I want to look you in the eye: I will not raise your taxes nor support a tax increase,” he said … at a town-hall-style meeting at the Wagner Company, a Caterpillar dealer. “I will not do it.”

Sigh...