U.S. Secretary of State Colin Powell made the legal and technical argument for going to war at the United Nations Wednesday. And there’s merit to what he had to say.

But here are some things he didn’t say that are driving the move to war as much as the satellite photographs and telephone intercepts:

The United States can’t afford to keep more than 200,000 troops in the Persian Gulf area indefinitely.

The buildup to a war has its own momentum and, at some point, it is inexorable. President Bush has probably passed that point. The United States cannot keep a huge number of troops just sitting there. One reason is that it is very expensive. Another is that the fighting capability of the troops will start to degrade over time. And, third, a prolonged presence of massive U.S. forces is a significant irritant and potentially destabilizing presence to the entire region. Recall that one major complaint from Arab militants, including al-Qaida, was the long-term presence of U.S. troops in Saudi Arabia.

A team of foreign policy experts at the Carnegie Endowment put out a report last week calling for an aggressive arms inspection regime over months or years, backed by the presence of a substantial U.S. force in the region to give it credibility. I thought it was an intriguing idea at first, but the more I examine it, the less I believe it is doable.

The uncertainty of whether there is going to be a war has damaged the economic recovery.

The market mavens will tell you that the markets abhor nothing so much as uncertainty. And the period before a war is always one of great uncertainty. Bush knows he must get the economy moving or it will damage his chances for re-election next year. Dragging out whether we are going to war is the last thing he wants to do to the economy now. While the administration has not come clean on the costs of the war — and, maybe even more significant, the costs of the postwar period — a decisive victory for United States’ forces will likely have a salutary short-term impact on the economy. That is, short term as in 2003 and 2004. The costs will not come back to haunt us until later.

It’s much better for Bush to fight the war now than in an election year.

Sorry if this sounds cynical, but I’ve been around politics long enough never to discount political motives. A decisive victory in Iraq this year will not any more guarantee Bush’s re-election in the fall of 2004 than did the triumph of U.S. forces in the Persian Gulf War of 1991 help his father win re-election in 1992. But if things go badly or prove to be more difficult than many of the so-called experts think, Bush still has time to secure the victory and get it behind him. Fighting a war in 2004 is high risk, even for the Bush high-stakes-style presidency. Better to get things done now and use 2004 to shore himself up in the manner that his father did not.

If all these seem like insubstantial reasons for going to war, so be it. That’s how history sometimes works. There’s no doubt in my mind that Saddam Hussein is a bad actor, and the world, let alone the Middle East, will be better off without him. No doubt, too, if we wait until he has nuclear weapons he will be much more difficult to deal with and the price for getting rid of him might be much higher.

Those who argue that Saddam can be deterred as was Josef Stalin (another evil tyrant who had nuclear weapons) are taking a huge risk, one that may not be prudent. The folks who know Saddam best, who have studied him for most of their professional lives, such as Ken Pollack of the Brookings Institution, say that he is too unpredictable and too unstable for us to rely on deterrence.

But Saddam is a few years away from obtaining nuclear weapons. The case for war now is more difficult to make. Powell Wednesday stuck to the text of U.N. Resolution 1441. And he’s on solid ground there. But have no doubt, Bush’s timing has as much to do with military and political expediency as adherence to any resolution.

James Klurfeld is editor of Newsday’s editorial pages.