FOR GEORGE BUSH, the resignation of long-time Supreme Court justice William Brennan is a gift of historic proportions.

The chance to appoint a young conservative such as David H. Souter '61 grants Bush the opportunity to give the court a rightward jolt that could last for decades. And with two other liberal justices ripe for retirement, a Bush Court could firmly implant the conservative agenda in the American judicial system.

But, like most gifts, Bush's gift has strings attached. Lots of strings.

When introducing Souter to the press late yesterday, Bush repeated ad nauseam that he would refuse to let his nominee be judged by an abortion litmus test. The Senate faces that flooded the airwaves later in the evening mimicked Bush's call for a non-issue-oriented confirmation process.

But because the topic of abortion so dominates the American agenda, it will be almost impossible for the Senate to "advise and consent" without reference to the divisive issue. And if the Senate ever finds itself debating the abortion issue--even in the form of a Supreme Court nominee--it could mean big trouble for the Republican party.

Republicans know this all too well. On Sunday, Republican leader Bob Dole urged Bush to avoid picking a nominee solely on the basis of his stance on abortion. He predicted that if the nominee favors overturning Roe v. Wade, "it's going to be a bloodbath getting the nomination confirmed."

Dole apparently meant that Bush's nominee could fall victim to a Republican/Democrat showdown. That is certainly a possibility. But if the Souter nomination does come down to abortion, it will be Senate Republicans who will be bathing in blood.

EVER SINCE last summer's Webster v. Reproductive Health Services decision, the Republican party has been in a precarious position on abortion. Although their national platform is strictly anti-abortion, Republican leaders have been wary of alienating their pro-choice candidates--some of whom are proven vote-getters and long-term incumbents.

For Republicans running in prochoice districts, an anti-abortion position is like a political scarlet letter. The New York State Republican Committee has actually dropped the anti-abortion cause from its agenda, saving its local candidates from the embarassment of ambiguity and political dissent.

So for more than a year, Republicans have been juggling a bungled mass of contradictory positions, their confused coalition veiled behind a curtain of rhetoric. They call it "tolerance." They call it a diveristy of ideas. Right-minded Democrats call it one big mess.

Whether or not abortion actually affects Souter's nomination will be of little consequence to the political fallout from a Senatorial floor fight. If the issue on the floor is abortion--as it likely will be--the vote on Souter will be perceived as a de facto vote on abortion.

Such a vote has the potential to reveal deep rifts in the Republican party. Americans will watch by the millions as their Senators effectively vote "Yes" or "No" on abortion.

If the Democrats can pry an abortion stance out of Souter, the ensuing floor fight will expose the rift within the Republican party over abortion. It is possible that a significant number of Republican senators--unwilling to vocally fight against abortion and possibly forfeit reelection victories--could defect from the party-line. It happened with taxes, and it can happen with abortion, especially with elections right down the road.

Such a Republican mutiny might prove fatal to the Souter nomination and to any number of wavering Senators. In a worst (or best) case scenario, such a fiasco could significantly undercut Bush's support, which is already descending from its once stratospheric heights.

BUSH COULD obviously see an abortion storm brewing in his Supreme Court nomination. As such, his selection of Souter was necessarily farsighted. A former State Supreme Court judge who has served on the Federal bench for only three months, Souter has almost no record of opinions on national issues like abortion.

Any nominee pushed by conservative White House Chief of Staff John Sununu and approved by pro-lifer Bush is unlikely to be pro-choice. But neither Souter nor Bush has chosen to disclose the nominee's opinion on Roe v. Wade, Bush dismissing the issue as unimportant to confirmation.

If Bush gets his way, Souter will follow the lead of Justice Sandra Day O'Connor and refuse to take a firm stand on such a specific issue during confirmation hearings. If the Democrats settle for this non-answer, they would save the Senate from a bloody floor fight but would incur the wrath of pro-choice activists everywhere. This could be lethal for Democrats and pro-choice Republicans alike.

The true test of Bush's popularity will be whether the president can see through Souter's nomination while avoiding a floor fight on abortion. If he can, the gift of a Supreme Court nomination will be a valuable one indeed, a gift that could last a political lifetime.

But if he can't, it could be a gift that costs some Republicans their political lives.