Washington ? The singular value of the presidential news conference, as it has evolved over the years, is the insight it offers into the workings of the mind of the chief executive. A secondary benefit is the way it forces the White House press corps to organize its own agenda.

In the session President Bush had with reporters last week, we learned something both compelling and disturbing about his mental process. And we learned something I found worrisome about the news media.

The lesson we could learn about Bush is the power — and the danger — that derive from his capacity to take even the most weighty presidential decisions and refine them down to the simplest terms.

It appears that the president chose to have a news conference, a rarity in his tenure, in order to show the American people and the world the logic that has led him to the brink of war. Whatever he was asked, Bush reiterated the almost formulaic set of propositions that leave him convinced, as he put it, that if Saddam Hussein “should be disarmed, and he’s not going to disarm, there’s only one way to disarm him” — war.

The antecedents of that simple, three-step syllogism are almost as bare-bones as the proposition itself. The United States was a victim of a devastating terrorist attack on Sept. 11, 2001. He, George Bush, has sworn an oath to protect his country from another such attack. Saddam Hussein, if left unchecked, could execute or facilitate an even more damaging assault with weapons of mass destruction. Saddam has defied repeated United Nations calls to disarm. His continued defiance is unacceptable. If the United Nations balks at removing him, the United States, for its own security, must do so.

The logical force of that argument is so compelling that it is no wonder Bush is described by everyone who deals with him as being completely convinced of the rightness of his own position.

The logic has been there in all of Bush’s speeches on the subject, going back to his United Nations address last autumn. What the news conference revealed was his extraordinary capacity to reject any efforts to put this matter in any broader context — his ability to simplify what otherwise would be a wrenching decision.

In the course of 20 questions, he was asked about a wide variety of considerations that might be thought relevant or important: the doubts of large numbers of his constituents; the opposition of major allies; the potential impact of breaking with the United Nations; the precedent he would set by invading a nation which has not attacked the United States; the reaction in the Middle East and the Muslim world, and the effect on the struggle against terrorism; the challenge of rebuilding a postwar Iraq and overseeing creation of a peaceful and stable democracy there; and the financial costs and economic consequences of such a war.

Each of those problems was dismissed in a word, a phrase or a paragraph, after which the president reverted to a restatement of what he sees as the essentials of the situation: The threat is real and unacceptable; if Saddam does not disarm, he must be disarmed.

When asked twice why his approach is so different to North Korea, which is publicly well on the way to achieving the atomic arsenal Iraq insists it does not have or seek, Bush refused to be led into a discussion of any inconsistencies. The Korean nuclear program is a regional problem, to be addressed through multilateral diplomacy, he said. Iraq must be disarmed. He has placed them in separate compartments of his mind, so don’t try to confuse him.

As candidate and as president, Bush often has demonstrated his belief that persuasion for him is often reduced to simple repetition. His is the rhetoric of the sound bite. It works well on the campaign trail, where different audiences in different locales need to hear the same message. However, when the same point is made over and over in the same words in a single news conference, his rhetoric tends to sound scripted, and the effect can be disquieting.

Blame some of it on a fixated press corps. I was astonished and dismayed that in their first opportunity to quiz the president in four months, not one question was asked about the shaky economy or the out-of-control federal budget. The very next day came news of the largest monthly jump in unemployment since the immediate aftermath of 9-11 and an official estimate that Bush’s budget proposals would add $2.7 trillion to the national debt in the next 10 years. An economically cushioned set of reporters seemingly couldn’t care less about this looming disaster. Talk about being out of touch!