Washington ? Under other circumstances, President Bush’s choice of Judge Samuel Alito for the Supreme Court would have been seen as a bold move by a strong president with a clear policy objective.

By choosing a man of superior intellectual heft and an indelible record of conservative views on major social issues, Bush would have been challenging his critics on the Democratic side to test their arguments in an arena where everything favored him – a Republican Senate.

But after the fiasco of the Harriet Miers nomination and the other reversals of recent days and weeks, the Alito nomination inevitably looks like a defensive move, a lunge for the lifeboat by an embattled president to secure what is left of his political base.

Instead of a consistent and principled approach to major decision-making, Bush’s efforts look like off-balance grabs for whatever policy rationales he can find.

The president’s opponents are emboldened by this performance, and his fellow partisans must increasingly wonder if they can afford to march to his command.

None of this is to suggest that Judge Alito will be – or should be – blocked from elevation to the seat of Sandra Day O’Connor. His record entitles him to the serious consideration and questioning he will undoubtedly receive from the Judiciary Committee.

But after Bush acquiesced in the conservative movement’s uproar denying Harriet Miers her chance for an up-or-down Senate vote, or even a hearing in that committee, there is no plausible way the White House can insist that every major judicial nominee deserves such a vote.

That was the rationale behind the threatened “nuclear option” in the Senate, the mid-session rule change that would have banned judicial filibusters. If the mass of Democrats and a few Republicans who may be dismayed by Alito’s stands on abortion and other issues can muster the 41 votes needed to sustain a filibuster under current rules, they now have precedent for using their power.

The conservative screamers who shot down Miers can argue they were fighting only for a “qualified” nominee, though it is plain that many of them wanted more – a guarantee that Miers would do their bidding and overrule Roe v. Wade. But whatever the rationale, the fact is that they short-circuited the confirmation process by raising hell with Bush. Certainly there can be no greater sin in a sizable bloc of sitting senators using long-standing Senate rules to stymie a nomination than a cabal of outsiders – a lynching squad of right-wing journalists, self-sanctified religious and moral organizations and other frustrated power-brokers -rolling over the president they all ostensibly support.

But the message that has been sent is that this president is surprisingly easy to roll. He came out of his election victory proclaiming that Social Security reform was his No. 1 priority. For six months, he stumped the country trying to sell his ideas – and failed. In retrospect, even Republicans said he misjudged the temper of the public by emphasizing privatization over solvency as the chief goal. He tried to isolate senior citizens from the battle, only to see them in the front lines. And he managed to unite the Democrats in opposition – something that their own leaders rarely can manage.

Next came Hurricane Katrina, which showed the whole country a case study in mismanagement by a White House supposedly under Harvard Business School-level discipline. Bush’s first decision post-Katrina was to suspend the law guaranteeing prevailing wages for reconstruction work. But that decision too was quickly reversed, in the face of pressure from Democrats, moderate Republicans and even the supposedly enfeebled labor movement.

And then came the Miers fiasco, with the dagger held by the president’s staunchest allies. It left in shambles any consistent claim that Bush employs serious principles in picking judges. A system that veers from an accomplished and studiously nonideological John Roberts, to a marginally credentialed and often confused-sounding Harriet Miers to an intellectual and experienced Samuel Alito with pronounced ideological views, is no system at all.

Politically, the president probably had no choice but to reach back for his conservative base in making the Alito nomination. At his current levels of support, he has no place else to go. But the latest Washington Post-ABC News poll contains a clear warning. Self-described conservatives made up only 31 percent of the electorate. Moderates numbered 44 percent. And the moderates were nearly exact opposites of the conservatives in their views toward Bush, disapproving of his job performance by a 38-61 percent margin, while conservatives approved 61-39.

The risks of a Supreme Court showdown fight are at least as great for Bush as for the Democrats.