BAGHDAD—A nameless Iraqi colonel brought in a broken man in bright yellow prison garb, wearing dusty flip flops and a week’s growth of beard below a long nose, with dull eyes that had given up all hope and defiance.

The colonel leaned the prisoner against a wall, facing in my direction. His hands were cuffed behind his back, beneath the words “Iraqi Correctional Facility” in Arabic. He was only maybe 10 feet from me.

He was an ISIS battalion commander, until he was caught in a raid south of Baghdad four months ago.

They say he refused to speak for four days, after a police raid captured him in his home, among his wife and five children. Then they showed him the evidence they had that convinced an Iraqi judge to issue an arrest warrant: photos of him and tape-recordings of his phone calls, ordering his followers to attack.

He was brought here to this nameless facility, and then brought late at night from his cell to this large un-heated conference room in a nondescript Iraqi government building I’d been driven to after 10 p.m. It was the first day I arrived back in Baghdad.

They brought him here to answer my questions, because they knew the last time I’d been here able to report on my own was in 2006, before a car bomb by ISIS-precursor al Qaeda of Iraq had hit my CBS News team. Lost in the blast: Army Capt. James Alex Funkhouser, his Iraqi translator “Sam,” and CBS News cameraman Paul Douglas and soundman James Brolan.

I didn’t know this was going to happen. All I knew was I’d had three hours of sleep before flying into Baghdad this very morning, and this was my fifth meeting of a long day. I was being taken to interview Iraqi counterterrorism officials, that much I knew. My cellphones were confiscated as we drove onto a sprawling, darkened, and mostly empty police base on a Thursday night ahead of the traditional Muslim Friday off, leaving me wondering what I was about to see.

We drove through a maze of blast walls before reaching the inner compound—the usual series of unimaginative, boxlike government buildings typical in Iraq. At the front door emblazoned with a sign urging officials to report corruption, I met a series of Iraqi officers who explained that they are among the main forces tasked with mapping, and dismantling, the so-called Islamic State in Iraq. (I was later told who they were, and where I was, but agreed not to publish those details.)

“We penetrated ISIS with operations so sophisticated the CIA could not conduct them,” said one of the senior officials, describing the hunt for intelligence key to capturing commanders like the one I was about to meet.

“Our first source was their women,” he bragged. “We were able to reach the senior leadership of ISIS through their wives, who gave us information willingly and are now leading free lives.”

I asked, how did you reach them?

“How did you find us?” He laughed in reply. I was to get no more details about the wives-turned-vengeful-Mata Haris.

To break the ice with this all-male Iraqi cadre, I’d pulled out a book I’d written long ago about the 2006 attack, with photos of the bomb’s aftermath and my extensive injuries. It made an impression.

About five minutes into my questioning, they looked at each other and said, do you want to meet one?

One what? I asked.

So now I had this former senior ISIS commander practically cowering against the wall, treated as a harmless afterthought as the men joked with each other around the table, as if they’d forgotten he was there.

He just waited.

The assembled counterterrorist professionals were debating whether I should be allowed to take his picture. They called a supervisor. It turned out he wasn’t yet convicted, so under their laws, couldn’t yet be photographed. This debate happened without my participation.

Then they uncuffed his hands and pulled them to the front and cuffed them again, and sat him down in a chair facing me.

Then they said, OK, you can ask whatever you want.

I started simple. What’s your name? It was relayed by my interpreter, who once conducted such interrogations for the U.S. military, so he quickly fell into a familiar pattern.

The prisoner quietly said his name was Abu Taha, father of Taha—a nom de guerre delivered by rote.

What’s your real name?

Malik Khamis Habib, came the quiet reply, no fight in his voice. Information came slowly, frequently interrupted by the triumphant counterterrorist officials displaying their beaten quarry.

I interrupted as politely as I could and asked if the prisoner could answer me directly. The prisoner was looking at me now.

He’d completed industrial studies, and had a government job. He thought he was 45 or 46. He could remember the year but not the month he was born. He was from a small village that didn’t keep track of needless details like that.

But he remembered the exact ages of his five children—children he said he hadn’t been able to see since his arrest—13, 11, 9, 5, and 3.

His wife is 40, named Nadia. She'd been allowed to visit him twice, and write letters delivered by the International Committee of the Red Cross, he said.

She was angry with him. She blamed him. He said she didn’t know he was a member of ISIS. He said he didn’t know how she would take care of his children. ISIS has an office that pays a stipend to families of the captured or dead, but he insisted she’d been paid nothing. The Iraqi officials did not believe him. The officials added that he was lucky he got visits at all because under Iraqi law, terrorists had no rights.

Why did you join ISIS? I asked.

“Someone from my neighborhood came to me. He explained we must make a change, that Shias were hurting Sunnis.”

Did you ever know a Sunni personally who was hurt by a Shia Muslim, I asked?

“No. Just rumors,” he admitted.

He was a member of the group for four years, working his way up from rank-and-file operator to his area’s battalion commander, commanding some 44 men. They didn’t behead, he said. They built improvised explosive devices to plant in roads to hit security forces.

And sometimes civilians, he added.

How many did you kill, I asked.

Forty, maybe 50, he said. Dozens and dozens, said the counterterrorist officials.

Did you see what happened after the bombs went off? How did you feel? I asked.

I don’t know, he said, looking at the floor again.

Who built the bombs, I asked. Outsiders? Or Iraqis?

Iraqis, he said.

My translator pushed him to explain his role in dispatching car bombs. He later told me this brought back some bad memories for him, too. Sporting a 101st Airborne sweatshirt and reciting proudly the designation of the 3rd Infantry Division unit he’d also served, he explained he’d lost five U.S. battle buddies in a car bomb that hit his team years earlier. He’d been thrown 50 feet, escaping with a concussion, broken bones, and the sadness of a survivor. He knew this prisoner had dispatched such car bombs against Iraqis, and he too wanted to know why.

“What do you want me to say,” the prisoner asked. “I destroyed myself. I destroyed my family.”

Why did others join, I asked?

“Some people want to fight the state. Some people want money,” he said. ISIS pays fairly well, or it used to, before the two-year-long Iraqi and coalition counteroffensive began to peel back territory and squeeze the group.

Do you think you will ever leave here, I asked.

“I don’t know.”

How do you feel about what you did?

“I gave all the information I had to the authorities, but I still feel guilty.”

He didn’t have a lot of information to offer. He knew who his district’s “prince” was, who ran four local battalions—including the one the prisoner commanded. But that’s about it. ISIS designs it that way so penetrating one cell doesn’t expose the whole network.

I wanted to ask if he’d been tortured. What else could so flatten a soul as his seemed crushed? But he would surely lie and say no, if it was true, or say yes, shaming the kangaroo court around him and surely leading to more torture. I thought of something else to ask.

Do you have a message for Americans?

“Yes,” he says, with the first sign of independence and a sense of purpose in the whole conversation. “ISIS is not Iraqi made. They are bloodthirsty. They kill innocent people. Their methods are wrong.”

Did you feel that way before you were captured, I asked.

No, he had the honesty to say. No.

One of the officials jumps up from his chair, grabs my book, and opens to the pictures of my skull shaved, swollen, and stitched, or another of my body on a stretcher, covered in medical paraphernalia keeping me alive.

“See this? This is what you did, with your car bombs. See this lady now? She has a message. We may get hurt, but we will get back to life.”

The bomber looks at the pictures, looks at me, and looks at the floor.

I don’t know what to say.

I ask him my last question: Do you have a message for Iraqis ISIS is trying to recruit, like they did you?

His voice has purpose again.

“Don’t join. Don’t be convinced by these words. They will destroy you, and your family.”

I say to him that I hope his honesty with these officials helps them figure out how to keep others from joining ISIS. I tell him I hope he sees his children again.

They lead him away.

One of the officials asks us back to his home. He is euphoric over the chance to parade a craven killer in front of a bomb survivor who happens to be an American reporter.

We meet his 9-year-old daughter and other family members, as he orders kebabs and shows us photos he has taken on his phone—a relentless series of selfies he has snapped with ISIS killers.

“This one chopped off heads. This one launched a truck bomb that killed 400 people in an instant. This one is the ISIS sheikh who taught Omar al Baghdadi himself.”

The official’s house is adorned with a picture of Iraqi Grand Ayatollah Ali al Sistani, the spiritual leader of Iraq’s Shiite community, next to Iran’s Grand Ayatollah Ruhollah Khomeini. Even his teacups have the double-tipped sword carried by the revered Shiite Imam Ali known as the Zulfiqar printed on them.

He is Shiite. The ISIS follower was Sunni. I ask if the Sunnis are right to be scared—Sunnis and Shiites have been at one another’s throats since at least the fall of Saddam Hussein. The official dismisses it as lies. He said Sunnis are lucky because their areas are being rebuilt as ISIS is being driven out, so they are getting new houses but Shiites are not. Having one’s home razed seems a steep price to pay for the hope of a rebuild thanks to international aid, but I am eating on his floor so I do not argue.

What do you think should happen to ISIS killers, he asks me, his daughter sitting near me and hanging on our every word.

I remember the Charleston church where a racist fanatic killed nine of their worshippers in hopes of triggering a race war, and how they turned his murderous act inside out by offering him forgiveness.

I described that to this Iraqi man, and said, I want to be like that.

I described also how I knew that the bombers who’d attacked us in 2006 were killed by a special-ops team the night of our attack, and that knowing the killers were dead didn’t make the grief over those lost or the survivor’s guilt any less.

He shook his head.

He explained that thousands of convicted ISIS fighters had been sentenced to death, and he was upset that the government hadn’t yet carried out the executions.

He said he thought those men, and the man I’d met that evening, should all be killed, an eye for an eye, a life for dozens of lives horribly taken.

He said the prisoner I’d met knew that he would never be released.

He knows he is going to be executed, the official said.

So that explained his numb, crushed obedience.

The thought gave me no peace.