WASHINGTON -- Try as he might at every forum, President George W. Bush still has not made a case for his claim that there is an urgent need for war against Iraq.

His frenzied effort to whip up public support and retain the backing of Congress verges on the hysterical.

Every time he speaks of the tyrannical Saddam Hussein, he depicts the Iraqi leader as more diabolical, more monstrous. That makes it all the harder to take Bush seriously when we recall that Republican leaders themselves once willingly did business with the so-called Butcher of Baghdad.

Is Bush afraid that Americans may question the reason for an attack now after 11 years in which Iraq has been contained, locked down with total surveillance from the air and hobbled by economic sanctions and bombings in its no-fly zones?

Many wonder what is driving Bush so headlong into war that he is pushing other issues -- the dismal economy, the stock market meltdown, corporate greed and skyrocketing health care costs -- off the table.

Does he really believe that Saddam, whom he now calls "a student of Stalin," is going to launch a war with the United States, a military colossus? Get real, Mr. President.

We already have thousands of American troops, along with fighter jets, missiles, tanks and gun ships stationed in the Persian Gulf, and four carriers are on the way.

So what is this straining-at-the-leash all about?

Speculation here and abroad is that Bush is driven by many motives. One is his desire for Republicans to win next month's elections. Another is his determination to get revenge against "the guy who tried to kill my father."

A third is said to be his secret goal of American control over the vast Iraqi oil reserves and, indeed, the whole Gulf region.

Bush also may be trying to test and make permanent his questionable doctrine of preemptive war, which allows the United States to attack any nation and depose any leader without immediate threat or provocation.

I ask you, is this policy really consistent with our tradition of morality?

For the past year, we in the White House press room had been told the administration could not establish a positive direct link between al-Qaida and Iraq or between the anthrax attacks and Iraq.

But in his speech Monday night in Cincinnati, Bush said Iraq had trained members of the terrorist group in "bomb-making, poisons and deadly gases."

Bush failed to mention that in the mid- to late-1980s, when his father was vice president in the Ronald Reagan administration, the United States allowed the Iraqis to buy from American suppliers equipment and other materials, including disease-producing bacteria that could be used to make such biological weapons as anthrax.

And, according to Newsweek, the United States knew from satellite imagery that Saddam was using poison gas on Kurdish rebels in 1988. In those days we were secretly glad when Iraq attacked Iran, which was our nemesis at the time.

Even though Bush is now playing up the alleged tie between Iraq and al-Qaida, and Americans are gung-ho to pursue the terrorist network, the public is ambivalent about going to war without strong allied support and without giving U.N. weapons inspectors a chance to examine Iraq's arsenal.

This Congress obviously has no institutional memory of the Vietnam War. Have we really recovered from that historic debacle? The free hand Congress would give the president under the pending joint resolution authorizes him "to use the armed forces of the United States as he determines to be necessary and appropriate."

That mandate is painfully reminiscent of the arbitrary power Congress bestowed on President Lyndon Johnson in August 1964 to step up the catastrophic war in Southeast Asia.

The lawmakers lived to regret it, and the anguish over the war tore our country apart. To most Americans, the war was a monumental mistake.

I remember all too well Johnson's news conferences, held as he and we reporters walked briskly around the South Lawn of the White House.

He would pull a tattered paper out of his pocket and show us how all but two senators voted for the Gulf of Tonkin resolution five days after dubious reports of attacks on two American battleships by two North Vietnamese boats.

That resolution allowed Johnson as commander-in-chief "to take all necessary measures to repel any armed attack against the forces of the United States and to prevent further aggression."

In the current debate on the Iraq resolution, Sen. Robert Byrd, D-W.Va., said he would vote against giving Bush a "blank check," which he denounced as taking away from Congress its constitutional prerogative to declare war.

Except for Byrd, there are few other dissenting voices in Congress and around the country. One, however, has been that of the Right Rev. John Bryson Chane, the Episcopal bishop of Washington, D.C., who has written a statement to his diocese opposing the war.

Chane grants that Iraq must be condemned for its previous "immoral and inhuman" military campaigns. But Chane urged Congress and the president "to resolve the crisis with Iraq using all non-violent means."

Chane quotes Alexis de Tocqueville, the 19th century French historian known for his classic study of the United States, who eloquently said, "America is great because America is good, and if America ever ceases to be good, it will cease to be great."

That is a prophecy worth pondering.

(Helen Thomas can be reached at 202-298-6920 or at the e-mail address helent@hearstdc.com)