Pity President Bush's able speechwriters as they craft this week's State of the Union address. You can be sure they will come up with fine words and eloquent phrases. What they cannot do is resolve the central contradiction of the Bush presidency.

George W. Bush has a choice. He can be a commanding and unifying leader who rallies the country behind the war on terrorism and major foreign policy endeavors. Or he can be a partisan and ideological leader who tries to transform domestic policy and politics.

He cannot succeed at both. Yet Bush is certain he can. He has decided that his will be a go-for-broke presidency, an administration in which no priority will give way to any other priority.

Politically, he wants to use the authority he gained after 9/11 to achieve an historic realignment to the benefit of the Republican Party. If that means using war and domestic security to batter the Democrats in the midterm congressional elections, so be it. If Democrats are now bitter, it's their problem, not his.

Domestically, he is pursuing a more ambitious conservative agenda than Ronald Reagan ever did. Bush is determined to do two things: first, tilt the tax code toward the interests of the well-off -- or, as Bush would see it, toward investors and entrepreneurs; and, second, create a long-term hole in the federal budget that will, over time, force deep cuts in domestic programs. If Bush wanted an economic "stimulus" plan that would shower the maximum number of benefits on the smallest number of the most financially comfortable Americans, he could hardly have done better than his proposal to eliminate the taxation of most dividends.

And then Bush would reorder the world. While he's cutting taxes, he's increasing military spending to bolster America's fighting forces. He wants to go to war with Iraq not only to rid Saddam Hussein of his dangerous weapons (and rid Iraq and the world of Hussein) but also to rearrange the politics of the Middle East. A war with Iraq would be no police action. If it comes to pass, the postwar phase will involve years of engagement, years of political and economic reconstruction. The president insists the United States can do all that, as well as pacify North Korea and still carry on the war against al Qaeda. And we hear nary a word about the potential for unintended consequences, the concept that is one of conservatism's greatest contributions to the public policy debate.

Now let's be clear: Conservatives are ecstatic over Bush's boldness. They praise him for betting the farm on the midterm elections and winning. They are pleasantly astonished at the ambition of Bush's tax proposals. They cheer his unapologetic swagger, embodied in down-home declarations such as last week's scoffing at the idea of giving U.N. weapons inspectors more time in Iraq: "This looks like a rerun of a bad movie and I'm not interested in watching it." And the more the wimpy Europeans complain -- especially those irritatingly unreliable French -- the more certain Bush's supporters are that he's on the right track.

There is only one problem with all this: It's not working.

The 21/2 months since the GOP's historic triumph in the midterm elections have been the most troubled of Bush's post-9/11 presidency. The polls offer one measure: Support for Bush's Iraq strategy is heading south. The Washington Post-ABC News Poll released last week found that only 50 percent of Americans approved of Bush's handling of "the situation with Iraq and Saddam Hussein," down from 58 percent a month ago. And on the domestic side, only 43 percent approved of his handling of the economy, a 7-point drop since December and the lowest grade of his presidency.

As for that "bad movie," seven of 10 respondents in The Post poll said they are willing to give the inspectors at least several more months; that includes four out of 10 who said that inspectors should have as much time as they want.

Now the president would say that he doesn't make decisions based on polls. But the polls reflect a genuine and significant problem: The more Bush has pursued an ideological agenda at home -- and the more he has used assertion rather than persuasion to press his case against Iraq -- the more he has split the country along partisan lines on foreign policy.

Bipartisan support for Bush's handling of the war on terrorism remains strong -- 71 percent in The Post's most recent survey -- but for the first time since the 9/11 attacks, a majority of Democrats (57 percent) oppose taking military action to overthrow Saddam Hussein.

To understand what the president has decided to throw away, it's worth recalling the depth of bipartisan unity that existed in the months after 9/11. I'll never forget calling a Democratic political consultant in the week after the attack and asking him his thoughts on Bush. This highly partisan Democrat replied: "I actually went into church and knelt down and prayed that he'd be successful. He's ours. He's all we've got. Pray God that he's going to do what's best for our country."

Such sentiments lasted well beyond the initial shock of the attacks, translating into genuine political support for Bush's foreign policy goals. There was hardly any dissent from his decision to wage war on the Taliban in Afghanistan -- partly, it should be said, because as a response to the aggression of 9/11, it was a war that made sense to most Americans.

Republicans might counter that Democrats were petrified, for their own political reasons, of saying anything negative about Bush. But this understates how authentic the feelings of national unity were at the time.

For example, it would not, in principle, have been unpatriotic for Democrats to press the administration hard and immediately for explanations of the intelligence breakdowns that preceded the attacks. Republicans, for their part, were not the least reluctant to blame the attacks on Bill Clinton, who had been out of office for eight months. Just days after the attacks, Republican Sen. Richard Shelby explicitly blamed Clinton for restrictions on the CIA's recruitment of informants overseas, saying that "the Clinton curbs have hindered the work of our human intelligence agents around the world." Shelby was not alone in voicing this view. But Democrats held their tongues for months.

Democratic bitterness is directly related to the sense of many in the party that they were played for suckers, especially in last year's elections. "The fact that the administration used 9/11 in the last election, that they seemed intent on using the president's role as commander in chief as a way of soliciting votes, has created a hardening of partisan lines that will be felt until the end of this administration," Rep. Chaka Fattah, a Democrat from Philadelphia, declared in a comment typical of his party's mood.

Sen. Dick Durbin of Illinois says that he and many fellow Democrats are still incensed that Bush and his party went after then-Sen. Max Cleland of Georgia for allegedly being soft on homeland security. Cleland's offense against the safety of the nation? He supported civil service protections that Bush opposed within the new homeland security department. "This is something that gnaws at us," Durbin said. "A decorated and disabled Vietnam veteran would be discredited because of his stand in the homeland security debate?"

Louisiana Sen. Mary Landrieu poured a little extra Tabasco on her comments about Cleland's defeat: "He left three limbs in Vietnam. He's already served his country in more ways than any of us ever will. The president came in with a very personal and very vicious attack, using the homeland security issue to unseat a man who fought on the Armed Services Committee to give the guys in the battlefield everything they need. It didn't mean a thing to this president."

Landrieu has her own issues with Bush. A Democratic hawk, she strongly supported him on Iraq, and called for even higher levels of defense spending. She also voted for his tax cut. Nonetheless, Bush threw everything he had into trying to defeat her in the December runoff that ensued after she failed to capture a majority of the vote in November.

She won anyway, and it's useful to hear her out. She won't be on the ballot again until 2008, so she can speak more plainly than some of her more politically vulnerable colleagues. "For Democrats who were trying to work with the president on national security issues and support a more hawkish stand than might seem natural for a Democrat, this president discounts it, ignores it, and acts as if it's not relevant," she said. "Any time the country is poised for war and about to engage on behalf of the security of the country, it's very important that the president make that the priority and make everything else come in second. Unfortunately, the president has done exactly the opposite of that."

Landrieu, like many of her colleagues, sees the country as increasingly polarized. "Unfortunately, the president has earned this polarization," she says. "It hasn't just happened. He pushed it to happen."

At this point, I can imagine Republicans and conservatively inclined readers saying: So what? Of course Landrieu is angry. Of course the Democrats are frustrated. But will any of it matter if everything works out well with Iraq, and if the economy comes back strong?

Well, sure. If things go perfectly for the next 21 months, Bush is likely to win reelection. And let's assume and hope that, if a war with Iraq takes place, Saddam Hussein is ousted in short order. The problem is, our commitment will then only have just begun. If Bush genuinely wants to create a new foreign policy, as Harry Truman did after World War II, does he not need to build the same bipartisan bridges that Truman did? As Landrieu's comments suggest, he has already blown up bridges to the very sort of Democrats on whom he is likely to depend.

Life being what it is, it's also likely that the next 21 months will not be perfect -- for Bush or for the country. Smart presidents engaged in large foreign policy projects understand the need to make sure the opposition stands with them in difficult times. At the beginning of World War II, Franklin Roosevelt was explicit about this: "Dr. New Deal," he declared, had given way to "Dr. Win the War." FDR jettisoned many New Deal dreams in order to unify the country against Nazi Germany and Imperial Japan.

Bush will go into a war with Iraq, if it happens, with far shallower support than his father had 12 years ago, despite the closely split congressional vote on the first Iraq war. Having used security issues for purely partisan purposes, this President Bush has diminished his ability to ask for support on purely patriotic grounds. He has no political net beneath him if something should go wrong. And by using his popularity on foreign affairs to push for domestic policies that Democrats genuinely despise, he has made those in the opposition who actually support his objectives abroad look like chumps.

That's the problem the president needs to confront in his State of the Union address on Tuesday. You wonder if he'll even try. E.J. Dionne is a twice-weekly columnist on The Post's op-ed page and a senior fellow at the Brookings Institution.