When President Bush began the blunt, brief speech that set the last clock running for war against Saddam Hussein, at 4 a.m. Kuwait time, a couple dozen officers and soldiers gathered around a television in the corner of a big double tent in the middle of 20,000 troops spread across 10 square miles of sand here. When Bush finished, there was no cheering, and everyone quietly turned and went back to work.

The 3rd Division has been preparing for this war for nearly a year and a half. Many of its troops have spent the better part of a year training for battle here. As the president spoke, one young female soldier methodically cleaned her M-16 spread out in pieces on paper towels on the map table. Reactions afterward reflected variations of personal expressions. But the viewpoint was generally one of welcome relief.

The division's chief of staff, John Sterling, who was just selected for promotion from colonel to brigadier general, and who has an operations man's meticulous nature, said: "It was an expected speech -- a required speech. If you're going to initiate war, you're required by international norms to inform the other side of your clear intention and to allow them to react and avert war. In a long series of benchmarks that have taken place over a long time here, this was one of the last benchmarks to check off."

Maj. Gen. Buford Blount, the division commander, who was told to prepare the division for war with Iraq when he took command a little more than a month after Sept. 11, said: "We are very ready." Brig. Gen. Lloyd Austin, the assistant division commander who will direct the assault, said: "This is war now. This is not a game. There won't be a playoff next year."

Pfc. Colin Wilson, 19, of Colorado Springs, Colo., said, "I'm happy now. I'm going to war before my 20th birthday. It's a beautiful thing. It beats sitting here, and it's the fastest way home."

There were worries. A primary one was the widely expected use by Saddam Hussein of chemical or biological weapons, which the Iraqi forces are believed to have the capacity to deliver, at least randomly and sporadically, through a limited number of missiles, buried explosives or their fairly considerable artillery.

"Put yourself in his shoes," said Austin. "He's facing the ultimate. This time it is not a matter of just quitting a country he invaded. This time we're going to kill that guy or imprison him for the rest of his life. He is a nut to begin with, so he may well attempt to strike at something he knows will give him fame. He wanted to achieve fame as a modern Saladin, a restorer of Arab empire, but he can't get that so he may think fame lies in at least killing some Americans."

The division's planning assumes some Iraqi use of chemical weapons. "As I watched the speech, I thought about Saddam," said Sterling. "His military forces have already faced us and lost to us, and they have not improved in the last 12 years. Chemical weapons are one of his few trumps."

Sterling worries that Hussein will order chemical attacks not in hopes of victory but rather to impress his own population and forces -- which intelligence reports say have been deserting at a brisk pace -- with the notion of his continued power.

The concerns, though, do not approach the idea that any use of chemicals might actually defeat or even seriously impede the American force. Blount says his concern is largely for "the psychological impact on our soldiers if it happens: I think they'll be nervous -- but they are well trained and I am sure they will hold." Concern for the Iraqi population is also paramount for Capt. Andrew Sims, the division's medical planner. "We would be able to handle our own casualties," said Sims. "But if he used chemicals near a population center of his own people, I couldn't even guess what the casualties might be."

There are other issues. Blount mentioned the danger of accidents in a force of about 9,000 vehicles that would try to move faster than any invasion in history. Austin mentions fratricidal casualties in an environment characterized by massive and varied American firepower. But while no commander expects serious organized resistance from most Iraqi forces, Sterling predicts fighting from elite forces and Baath Party apparatchiks "who are less worried about what Americans will do to them than what their fellow Iraqis will do."

All real worries, but in the terms of war, worries are luxuries. The overall view is expressed by Austin: "We can see them. And what we can see, we can hit, and what we can hit, we can kill, and the kill will be catastrophic." And by Sterling: "A thousand things can happen to make life absolutely miserable for us. There is not one thing that can happen to stop us."