With our troops apparently on the verge of what has long been billed as the penultimate struggle of Gulf War II - the battle for Baghdad - the question naturally arises: Will they have to face weapons of mass destruction?

At the end of last week American troops found thousands of boxes of an unknown white power (later tested and believed to be an explosive), nerve-gas antidote and chemical-warfare documents at complex south of Baghdad. Earlier last week, 3,000 chemical suits were found in an Iraqi hospital in Nasiriyah. It seemed the closer our troops got to Baghdad, the more they were forced to confront evidence that non-conventional chemical and biological threats - the favored weapons of terrorist groups worldwide - are still a real possibility.

It's clear that Saddam Hussein has been backed into a corner by coalition forces that have no intention of leaving him in power. As Defense Secretary Donald Rumsfeld has said, the Iraqi dictator can expect "no deal" at the 11th hour. If it's his last stand and he does use these weapons, will there be mass casualties and how prepared are our troops?

Whether Saddam will use biological or chemical weapons against coalition forces depends on a number of factors. Obviously, Iraqi conventional forces don't stand a chance against the coalition troops arrayed around him. Late last week, it was still undetermined whether Saddam was alive and if he gave his leadership orders to use these weapons of mass destruction (or the discretion to decide to use them) in the event of a communications blackout.

What we do know is that Saddam has used chemical weapons in the past. During the Iran-Iraq war, he used mustard gas and sarin gas on Iranian troops. Worse, he has used deadly chemical agents on his own countrymen, killing over 5,000 men, women and children. A leader who treats non-combatants in this fashion is capable of any atrocity - and our troops are well aware of it.

We also know that he has produced large quantities of these weapons and that they have yet to be accounted for. The list includes 25,000 liters of anthrax, 38,000 liters of botulinum toxin and 500 tons of mustard, sarin and VX nerve gas. There are also 30,000 missiles and short-range rockets that Iraq has failed to account for. We know Saddam had all of this. The report he submitted to U.N. inspectors in December, which was to have declared all weapons of mass destruction, didn't mention any of that.

Of course, that doesn't mean Saddam is eager to use these weapons, if only because their use would prove, once and for all, that he's been lying. The use of chemical weapons would be a last-ditch effort by Iraq. Any remaining world support would vanish when the first artillery shell carrying VX or sarin nerve gas is launched.

But if these weapons are used, U.S. troops are well prepared. Any non-conventional threat would probably have little effect on those fighting on the front line. They've been vaccinated for various biological agents. They have their gas masks. They have chemical and biological suits. They have penlike devices they can use to inject themselves with antidotes to many nerve agents. The tanks and attack vehicles they're driving have filtration devices to purify outside air.

We recently used a Department of Defense computer model that analyzes the consequence of a nuclear, biological or chemical attack (one that accounts for population and weather) to consider one possible scenario. The scenario showed 75 artillery rounds carrying VX nerve gas launched within 10 miles outside of Baghdad under current weather conditions would have little or no effect on coalition troops, but up to 2,200 unprotected civilian living along the Tigris River would be killed and another 33,000 could be injured.

Another danger would be posed to the regular Iraqi army. Depending on the weather, they could find themselves being exposed to an agent released by their own leadership. The ill-prepared Iraqi army is spread throughout Iraq with little or no means of communication, thus making them vulnerable to a breeze carrying sarin gas or some other nerve agent.

Unfortunately, they wouldn't be alone. Such an attack could affect tens of thousands of people, depending on the weather and how the wind is blowing during a release. Most of those killed and badly hurt by whatever poisons Saddam uses would undoubtedly be the men, women and children who live in and around Baghdad.

As Saddam well knows, civilians have no protection against chemical or biological assault. But coalition troops do. Which raises a chilling possibility: That the Iraqi dictator could well decide, now that no hope of escape exists for him and his inner circle, to deploy the ultimate "scorched earth" defense. If he does, God help the poor people of Iraq.