The United States is moving closer to a war with Iraq, as U.S. President George W. Bush made clear yesterday at the United Nations.

Many analysts have bought the administration’s label of it as a pre-emptive war. But that’s not accurate, as old Cold War hawks in the Defense Department surely know. It claims a particular kind of moral high ground that in this case is lacking.

In strategic analysis, a pre-emptive war arises in a spiral of crisis escalation when one side decides there is a very great risk that its adversary will attack within days or hours — and that the attack will cripple its ability to defend itself or retaliate. American and Soviet planners feared each other’s many nuclear-tipped missiles.

Pre-emptive war would have been a desperate effort of self-preservation. Some military men advised it during the Cuban Missile Crisis; Robert Kennedy and Dean Rusk successfully rebutted. Only three cases over the past two centuries more or less fit the description, the most recent being Israel under imminent threat of Arab attack in 1967. Pre-emptive wars are rare because of the immense costs, at home and internationally, incurred if there is any doubt about the threat’s gravity and immediacy.

Getting rid of Saddam Hussein is a worthy goal. Yet his Iraq does not remotely pose a danger such as Israel or the Cold War superpowers faced. We have seen no evidence that he currently has even one nuclear weapon, and far more biological and chemical weapons than anyone claims for him still could not prevent devastating American retaliation. Nor is there evidence that he is planning an immediate attack.

Its advocates might call it a preventive war — but that means a war launched by a declining power to meet a growing but not immediate threat, a shift in the balance of power produced by a rising country of nearly equal military capability.

Presumably they don’t really want to imply that U.S. military power is declining, or that Iraq is a near-equal.

Of about 20 preventive wars launched by great powers over more than three centuries, none was initiated by a democracy. Democratic leaders are typically restrained by popular fears of costly and risky behavior, and by expectations that the voters will toss them out of office if they overreach.

Perhaps that’s why we have heard so little from the administration about the costs, in blood and treasure, of fighting and winning such a war, and cleaning up the mess in a defeated Iraq. Democracies typically prefer to create a defensive alliance, relying on deterrence and containment, as the United States did against a far more deadly Cold War danger.

Perhaps semantic slipperiness betrays logical sloppiness. Maybe the threat of war, whatever the adjective, is meant to encourage a coup: just let the rest of Iraq know what devastation will occur if Saddam Hussein stays in power, and set a time limit. If that worked, it would bring the gains of war without fighting one. But just what would compliance mean? Bush has laid out a long list of demands, amounting to fundamental change in the character of the regime as well as its leader. Suppose the coup leader was just another Iraqi general, with little claim to democracy or less vicious foreign policies. What would the administration do then?

Whatever the label, an invasion or massive bombing campaign against Iraq will constitute a first strike against a regime that, however evil its history and intentions, does not yet have the ability to launch an aggressive war.

To be remotely acceptable to the world, an attack on Iraq would need to be approved by Congress and the United Nations. Indeed, Bush just called for U.N. Security Council approval. By various means of persuasion and influence he may well get both to assent.

That will be good, provided that the long-run implications of such an attack, and those of alternative policies, are considered fully and openly. Assent alone would not guarantee that the act was prudent.

Bruce Russett is the Dean Acheson Professor of International Relations at Yale University.