The San Bernardino mass shooting was neither the biggest nor the most sophisticated terrorist attack on our shores, but it had to be the most disturbing.

If Syed Rizwan Farook and Tashfeen Malik planned the horror on their own—and quite likely they did—they were about to prove themselves as diabolical and sociopathic as ISIS at its worst when they dropped off their 6-month-old daughter with Farook’s mother on Wednesday morning.

The Southern California couple then drove to a holiday party being held by Farook’s fellow San Bernardino County health workers in a rented hall at a center for the disabled. Malik seems to have waited outside as Farook joined the festivities just as he had the previous year’s holiday party in the same hall. These same colleagues had thrown him a baby shower only a few months before, and they had more recently welcomed him back from paternity leave.

Farook sat for a few minutes. Some 80 other colleagues had arrived. There was a Christmas tree. All the tables were decorated. The luncheon was about to begin when he abruptly left the hall, puzzling an office cubicle mate.

Farook reappeared about a half-hour later with the Pakistani woman he had originally met through an online Muslim matrimonial site he joined in August 2013. He had subsequently married her at the Black Stone in the center of the Grand Mosque in Mecca. He settled with her back home in San Bernardino County, and there had been a nice wedding party at the local Islamic center. More than one person would speak of them as having lived the American dream on a good salary in a comfy apartment.

That all turned to an absolute nightmare as the couple materialized in the hall’s entrance, both clad in black tactical outfits, both holding .223 caliber assault rifles. They proceeded to fire between 65 and 75 rounds into the holiday crowd of people who had on another day helped celebrate their child’s impending arrival into the world.

After killing 14 and wounding 19, the couple withdrew to what would initially be described only as a dark-colored SUV and drove away with a lack of haste that surprised one witness. They left behind an explosive device that Farook might well have used part of his paternity leave to construct, building a bomb when he was supposed to be forging a bond with his child.

The detonator was reportedly fashioned with a remote-control toy, as suggested by al Qaeda’s online magazine, Inspire, and likely used in the Boston Marathon bombs. The toy that Farook and Malik had chosen for their particular bomb was a yellow sports car.

In this instance, the plan was apparently not only to kill more of Farook’s co-workers but also any number of the cops who raced to the scene and dashed fearlessly into the hall.

Fortunately, the device failed to go off. One police expert suggested that there might have been some kind of electronic interference or that the couple may have been too far away when they tried to detonate it.

The more likely explanation is that the hall’s sprinkler system had been triggered, apparently by one of the couple’s bullets. The resulting deluge almost certainly surprised the killers. It also might have soaked the remote control electronics.

Among the officers who otherwise might have been killed was Lt. Mike Madden, one of the first four to arrive. A lesson of the Columbine massacre was that the police need to go in right away to prevent anybody else from being hurt. Madden reasoned when he entered the conference center that he had arrived just moments after the shooting.

“There was the smell of gunpowder in the air,” he would later say at a press conference.

He saw people who were beyond saving.

“Victims who were obviously deceased,” he later said. “Unspeakable carnage.”

He saw the total panic in the faces of the living. He heard people who were in desperate need of aid.

“The moans and cries,” he recalled. “It was very loud.”

Water was spraying from the sprinklers overhead and fire alarms were sounding, and everywhere the eyes went they beheld what should have never been.

“What you’re seeing, what you’re hearing, what you’re smelling,” Madden remembered. “Surreal.”

Some 50 survivors were huddled on the far side of the room, too terrorized to budge when the officers called to them.

“We had to tell them to come to us, come to us,” Madden would report.

One of the survivors came, and then they all came. There was no way of knowing if the killers were still in the building. A cellphone video recorded a cop—apparently a San Bernardino sheriff’s deputy—escorting some of the survivors to safety. His words are worth remembering the next time somebody condemns the police in general.

“Try to relax, everybody, try to relax,” he told them. “I’ll take a bullet before you do, that’s for damn sure.”

Not on the video was a witness who reported something that one of the responding cops immediately put over the radio. The cop relayed that the witness had been sitting next to a fellow county worker who had been “acting a little weird” and then suddenly left the hall.

“Thirty minutes later, the shooting happens,” the cop said.

The cop gave the name provided by the witness.

“Syed Farook.”

Another cop radioed that a follow-up on the tip had begun with the basics.

“That Syed guy’s name and date of birth…”

A third cop recalled aloud that one of the detectives had been “working up that name for something last week.”

“I’ll have to check,” he said.

Somebody else reported that the LAPD may have made a recent inquiry about Farook.

The San Bernardino police now quickly determined two possible residences for Farook and set up surveillance on both.

One of the teams radioed a report concerning a vehicle that passed one of the addresses.

“Soft going by location.”

That meant slow, as if the driver were cautiously checking to see if the coast was clear.

“Black SUV, Utah plates, late model, probably 2014, front windows not tinted,” the cops on the scene further reported.

The police had by then determined that Farook had rented a black SUV such as had been reported leaving the killing scene, such as was now proceeding away from the residence.

The police followed. The black SUV suddenly accelerated from soft to careening.

“East at a high rate of speed,” a cop reported. “We are in pursuit of the suspect vehicle. We have shots fired out the back window.”

The cops’ voices on the radio remained remarkable even as shots could be clearly heard in the background.

“Multiple shots fired,” a cop reported.

Also in the background were the sirens of ever more cops racing toward the most mortal danger. An officer was hit, apparently by a ricochet, but the wound was not serious. The danger remained.

“We have the suspect vehicle stopped,” a cop announced. “We need a Bearcat!”

A Bearcat being an armored car. Three responded, but the shooting was done. The occupants of the car had fired 76 rifle rounds at the police. A total of 23 officers had fired 380 rounds in response.

“We have one down outside the car,” a cop reported “One down inside the car.”

The SUV’s emergency lights were on and kept flashing. The windshield wipers periodically worked in the rainless afternoon. A body could be seen sprawled in the street, a rifle nearby. Another body was in the back. There was also a second rifle, along with two 9 mm handguns, 1,400 more rounds of .223 ammunition, and 200 rounds of 9 mm ammunition.

Another 2,500 rifle rounds and 2,000 pistol rounds were discovered when police armed with a search warrant went through the house where the couple who seemed to be living the American dream had been concocting a nightmare.

The couple had not been bent on suicide. They had done everything they could to get away after the killings, and there is no way of knowing what else they may have been plotting. There have been reports that they were in touch with Islamist extremists, and perhaps that is what prompted the LAPD to have taken an interest in Farook.

Part of the reason for leaving the bomb in the conference center may have been the hope it would aid their escape. Police now found in their home a dozen more pipe bombs, which, like the one at the murder scene, were identical to those that al Qaeda’s magazine depicted, along with step–by-step instructions on “How to Build a Bomb in the Kitchen of Your Mom.”

Only, Malik was a mom. And Farook was a dad. The thought of their 6-month-old daughter brought cause for thanks that mom and dad did not collect her from grandma and have her in the car with them when they encountered the police.

Along with Johnson’s Head-to-Toe Baby Wash and Pampers Swaddlers Diapers, the mom’s baby registry with Target (“Tashfeen’s Baby Registry”) lists an Evenflo Tribute Convertible Car Seat. That would suggest some awareness of child safety, but there seems next to no chance the couple would have refrained from firing at pursuing officers out of concern for their daughter.

And the police who were being fired upon would have had no way of knowing there was a tiny child behind those tinted windows in the back. Nobody would have felt worse than the cops if the child had come to harm.

The child survived, the absolutely innocent beginning and end to her mom and dad’s diabolical plot. Other plots have reminded us that we are at war. This one tells us that we are in a war like no other, a war in which a couple drops their baby with grandma, then goes to a holiday party to murder co-workers who not long ago threw them a baby shower.

A shudder accompanies the question of whether the murdered included anybody who bought one of the items on Tashfeen’s Baby Registry.

Updated 9:40 p.m. Dec. 4, 2015