Lt. Col. David Pere paced up and down the cramped confines of the Marine combat operations center like a caged animal. One second he was barking into the microphone attached to his wireless headset. The next he was shouting orders at an officer a few feet away.

The situation facing Pere, the senior watch officer in the Marines' war room, appeared as dire as any in a week of war. Predator and U-2 surveillance planes had detected an Ababil-100 missile poised to launch at U.S. military bases in Kuwait. There was reason to suspect the missile carried chemical weapons and Patriot antimissile batteries were temporarily off line.

The bases in Kuwait had been put on alert and B-52 bombers were overhead. In a matter of minutes, they could take out the missile launcher. Tension mounted. But then chemical weapons specialists in the back of the room looked up from their computer displays showing the air currents and possible plume. Any strike on the chemical weapons, they concluded, could result in 4,000 civilian casualties.

It was a day of high-stakes decision-making in the six-section tent that serves as the nerve center of the Marine and British ground war in Iraq. From here, Marine commanders oversee a battlefield with more than 85,000 troops, organizing the movement of thousands of vehicles over hundreds of miles of hostile territory, responding to ambushes and directing bombardments.

The missile scare was one of a flurry that came at the same time. As he was struggling with the Ababil report, Pere got word that a 200-vehicle Marine convoy had come under attack by mortars and rocket-propelled grenades north of Nasiriyah. Pere put the Ababil on hold while he tried to figure out that situation. Eventually, both crises would be dealt with, but the scene underscored the tense and often difficult environment in which military decision-making takes place.

"This is Lieutenant Colonel Pere," he said into the telephone. "Now where are you?

He stared down. The answer was confused. "Slow down," he ordered. "I can't understand you. Where are you now? Are you with the convoy?"

A minute later, Pere put the phone down. "We need to get Cobras up there right now!" The best way to save the convoy, he knew, was to send the Marines' attack helicopters, the AH-1 Cobra gunships.

Across the room, Col. Paddy Gough, the Marines' deputy operations chief and highest-ranking officer in the center, was still focused on the Ababil. "Hey, two," he called out to G-2, the intelligence section. "How can you tell these guys are in chem suits?" He sat with an analyst to get an answer.

Pere, who as senior watch officer was running the room, wanted the dozens of officers in the combat operations center to concentrate on the convoy and grabbed a microphone. "Attention in the COC," he called out, demanding their attention. "The number one priority right now is to get Cobras up there to that grid location to support the convoy. Not the Ababil."

No one voiced disagreement and everyone went to work dispatching the choppers. But Gough called out to Pere, reminding him not to forget the Ababil. "Hey, Dave, as a lesser priority, we are going to strike the [expletive] out of it, right?"

Right about then, new information was coming in about the Ababil. The latest surveillance analysis concluded that the vehicle next to it was not a decontamination truck, as originally thought, and the men hovering nearby were not in chemical protection suits. The telltale clues they thought indicated it was a chemical missile were not telltale clues after all.

The officers in the operations center had little time to digest this. Other surveillance pictures now appeared on one of the four giant display screens at the front of the center. Artillery batteries had been spotted; as the officers studied the imagery, they found the topography frighteningly familiar.

"That's where we are, sir," an officer warned Pere. Pere scoffed. Artillery just outside this secret base? "I can't believe that, with all the [helicopters] that we have flying here." He ordered a force protection squad to check it out.

Another officer reported again on the convoy. "They've got a section of Cobras they're sending now," he told Pere.

"What time on target?" Pere asked.

"Don't know."

Pere was worried. Dressed in a green Marine T-shirt with suspenders holding up the trousers of his chemical protection suit, he strode around the command center with an unlit cigar in one hand and a mug of coffee in the other. A 41-year-old North Carolina native who now considers San Diego home, Pere is not the biggest man in the room. But no one ignores him.

While the Cobras were lifting off, Pere got on the telephone with officers at Task Force Tarawa, south of the ambushed convoy. "We sent that convoy out there," he told them. "It's getting killed." He asked them to send a reaction force and hung up.

Then he turned his attention back to the artillery gun that might be close by. "Did you talk to the force protection guys and have them send somebody out there?" he asked an officer sitting in front of him.

"Not yet, sir, I haven't had the time."

"Somebody's not getting their [expletive] Tootsie Roll tonight!" Pere called out.

By now, intelligence analysts had concluded that the Ababil missile was not a chemical threat. But the Marines decided to proceed with the airstrike to get rid of the launcher.

Suddenly an officer called out. "Hey, we got a team compromised!"

He meant that someone had discovered a Force Reconnaissance team of scouts who roam around behind enemy lines keeping track of Iraqi forces.

Pere immediately began to plan to get them out. "Is it an emergency, is it routine or is it practice?" he demanded.

Gough, meanwhile, remained focused on the missile. "Brian," he called out to Lt. Col. Brian Delahaut, "what's the status of the Ababil?"

"They were three minutes away," Delahaut answered, but then the B-52s veered off. Concern over their weaponry had necessitated a change to F-15 fighter planes, which were now heading to the site.

Pere was thinking about the reconnaissance scouts. "I need a grid location for that recon team. "I mean right now!" he shouted. "We need to push air over to that recon team. They're being compromised in real time."

An intelligence officer carrying in news from the reconnaissance team ran in. "There are troops massing there," he reported.

Pere was beside himself. "What the [expletive] hell else is going to happen?" Perhaps he shouldn't have asked. A couple minutes later, someone shouted out, "Gas! Gas!"

Suddenly the command center erupted. The fight they had been waging on their screens and telephones was suddenly being brought to them. Everyone in the room dropped everything and threw on their gas masks in preparation for a chemical weapons attack. Everyone, that is, except Pere, who remained on the telephone.

"This is not a drill!" someone said.

"Where's NBC?" someone else asked, referring to the nuclear-biological-chemical team.

"We're trying to find out right now."

Pere, still maskless, was shouting out to the other officers. "Hey, where are those Cobras?"

Five minutes later, the all-clear signal was given. It was a false alarm. The masks came off, and everyone returned to work.

Lt. Gen. James T. Conway, the Marine commander in the region, strode in a few minutes later and got a briefing on everything going on. Gough told him about the reconnaissance team.

"Birds on the way yet?" Conway asked.

"Not yet," Gough said.

How about the convoy, Conway asked.

Cobras were in the air, Gough reported.

"Do they have any losses?"

Pere shook his head no.

Gough turned his attention back to the reconnaissance team and what aircraft were available to pull the team out. "Brian, what do we got that can be diverted?"

"The recon team, they're saying they don't want to be extracted," Delahaut reported.

Gough couldn't believe it and cursed. They didn't want to be evacuated?

Another officer explained that while the recon team had been seen by shepherds, it was not near enemy troops and felt it had not been compromised. "They're fine where they're at," the officer relayed.

"Okay," said Col. Dennis Judge, the current-operations officer, "we're putting the extract on hold now."

Pere, still thinking about the convoy, turned back to an air officer. "Hey," he said softly, "I'm concerned about the Cobras. He told me 10 minutes."

"Yes, sir, that was six minutes ago."

A report came back from the airstrike on the missile. The F-15s found no Ababil, but did spot three Al Samoud missiles.

Just then, what sounded like an artillery explosion could be heard through the walls of the tent. "Somebody find out what that is!" ordered Judge.

Pere asked again about the helicopters. The general had insisted that the convoy, loaded with fuel, supplies and engineering equipment, must get through. Marine units to the north and south were now sending in teams to help. Pere suggested they might need Cobras to cover the entire convoy, which now stretched over 12 miles.

"Trouble is," sighed Gough, "right now we're running on empty."

More information began coming in. The artillery they thought they had spotted near the base turned out to be a misinterpretation of the map. The explosion had come from another base several miles away, where it could have been someone destroying leftover ordnance. The Patriots were now back on line. And Marine F/A-18s had just bombed the three Al Samouds.

Pere wanted to know if they had hit the target. He asked what a British surveillance drone had seen.

"We don't know yet," British Maj. Nigel Williams answered.

"I need to see three Samouds destroyed," Pere insisted.