WHEN PRESIDENT BUSH HINTED LAST week that he might be willing to raise the payroll tax cap to "pay for" Social Security reform, he opened the door to the largest federal tax increase endorsed by a Republican since George Bush Sr.'s "read my lips" debacle 15 years ago.

The 12.4 percent Social Security payroll tax is now levied only on the first $90,000 a worker makes each year. What President Bush said was that raising the cap (to perhaps $125,000 or even $200,000) was "on the table." This was a strategic blunder of the first order. Now even the strongest advocates of Social Security personal accounts are wondering what hefty price will have to be paid to enact them. And while this move was seen as a tactical device by the White House to keep the Social Security debate moving forward, in fact it is a serious setback. House majority leader Tom DeLay and others in the Republican leadership in Congress have rightly declared that any tax hike to "pay for" Social Security reform is dead on arrival, especially in the more conservative House.

Bush may gain a few Democratic votes by agreeing to raise taxes, but it appears he would lose far more Republicans in the bargain. In other words, this proposal is a net subtraction of votes for personal accounts.

Worse yet, by talking of higher taxes in exchange for Social Security reform, the White House is only reinforcing the concern among House Republicans in tough districts that this debate could become

A quick glance at George W. Bush's governing style during his first term reveals that whenever he reaches out to congressional Democrats, the result has been legislation that maims taxpayers and divides the Republican party down the middle. That is what happened with the ill-fated $1 trillion Medicare prescription drug fight of 2003. Conservatives split off from the president, and enough moderate Democrats gave Bush the margin for "victory." The term "victory" is in quotation marks because it is now universally acknowledged that the prescription drug bill is a fiscal time bomb, with the costs already exploding in the 18 months since it was passed.

An even more ominous analogy is the No Child Left Behind education bill. This passed in 2001 with lots of Democratic votes, including support from Ted Kennedy. The education bill ended up massively expanding education spending, and it sanctified the federal presence in school policy. Worst of all, the one desired conservative feature, school choice, was excised in the process.

The danger now is that Bush, who wants a legacy "victory" on Social Security, will ultimately sign a Social Security bill that raises taxes and drops or guts personal accounts. On Social Security, Bush is arguing for less bureaucracy and more individual financial choice, and those are attractive concepts, particularly to young voters. Polls reveal consistently that the public understands that the Social Security system needs to be modernized (though they reject the term "crisis") and that those who argue for doing nothing (most of the Democratic party leadership) are the enemies of progress. Bush got a huge boost this week from Alan Greenspan, who acknowledged (1) that Social Security's finances are in desperately poor condition, and (2) that private accounts can be very beneficial to young workers. But Bush's talk of higher taxes stepped on that helpful headline.