"I think notifying a young pregnant widow is the most difficult thing," Lt. Col. Stephen Beck told CBS News' David Martin.
For two years, Lt. Col. Beck cast a long shadow as the dreaded knock on the door.
"I'm delivering the worst news in the world that could possibly…that a family could possibly receive," Beck said, "yet I have to do that with enough grace to build a relationship of…a caring relationship with that family, to guide them through what is going to be the worst months of their lives."
He has knocked on 13 doors.
"I remember them all. I remember the doors. I remember the walk to the door. I remember the prayers before the walk to the door. I remember them all."
For Melissa Givens, the knock came on May 1, 2003. She was eight months pregnant and President Bush was about to deliver his "mission accomplished" speech.
"I'm watchin' it," Givens remembers, "waiting for him to come on, and I turn around and there's two guys standing at my door. And they wanted me to come to the door because they regretted to inform me that he drowned in the desert."
Jesse Givens had been trapped in his tank when it went into a canal. He was the 139th soldier to die in a war which has now claimed 3900 lives.
"He wasn't soldier 139," Givens said. "He was my best friend. He was Dakota's dad. He was his mom's, you know, baby. He was so much to so many and we lost him and we loved him and we still love him."
"At the time, 139, everybody was saying how low the casualties were," Martin said.
"It must not have felt low to you."
"No," Givens agreed, "No, cause mine's gone."
Jesse, a tank driver with the 3rd Armored Cavalry Regiment, left home less than three weeks before he was killed.
"Do you remember the last thing you said?" Martin asked Givens.
"Good bye. Don't make me rich," she answered.
"Don't make me rich."
"We kept joking, because of the life insurance," she recalled.
"So if you could joke about it, maybe you weren't very worried that it really was going to happen," Martin asked.
"I wasn't," she said.
But Jesse was. "I've been getting bad feelings" he wrote in a letter to be opened after his death. "I hope someday you will understand why I didn't come home," he told his then five year old son Dakota.
And to his wife, "Please find it in your heart to forgive me for leaving you alone."
"I have a lot of guilt about being the parent that, that is still here," Givens said. "I haven't always been a great parent. And he was great."
28 days after Jesse died, their child, Carson, was born.
"He's a blessing to look at cause he looks like his dad," Givens said. "He's got his eyes and his passion. But then, at the same time, you know, I know every time I look at Carson…if Carson's two years old, Jesse's been dead two years and 28 days."
Carson's older brother, Dakota, is now 10.
"You ever talk with Carson about your dad?" Martin asked Dakota.
"All the time."
"Really? What do you tell Carson?"
"That he always wanted to meet Carson and see him."
"Does Carson get sad sometimes?" Martin asked.
"He didn't used to. Now he is."
"About his dad?"
"He just started to figure out what it means when you go up to Heaven," said Dakota.
"Do you get sad sometimes?"
"Oh, sort of. I'm kind of not crying as much as I used to. I cry a little bit. I don't cry like a lot."
"I think any military leader would be only honest to say that, that he's constantly asking, "Is this worth it?" and I've asked myself that at various times," General David Petraeus told Martin.
General Petraeus commanded a division during the initial invasion and now, on his third tour, is commander of all forces in Iraq. He knows many of the 3900 fallen Americans personally.
"Well, certainly in the hundreds. And, and obviously, the, the closer you are, the more you feel it," Patraeus said. "But I think it doesn't matter. You may be…I think it was John Donne who said, you know, "Ask not for whom the bell tolls, it tolls for thee. Any man's loss diminishes me," I think is roughly what it was. And that is very, very true for that family of those who are in uniform."
General Petraeus says he feels a special bond to Staff Sergeant Paul Johnson of the 82nd Airborne who was killed in 2003 outside Fallujah. They served together back in the States and in Bosnia.
"I don't know whether I regard him as a son, a brother, whatever it was. His loss just hit really, really…very, very hard."
And the General says he will never forget one especially tragic night in 2003 when 17 soldiers died after two helicopters in his 101st Airborne Division collided in mid-air.
"It's something you never get hardened to as a leader," Petraeus said.
Most of us are like passengers on that airplane. We catch only fleeting glimpses of the agonies military families endure.
"If half of the members of Congress had to wake up every morning worrying about a loved one at risk then they would solve this problem pretty quickly," said Senator Jim Webb.
Senator Webb was running for Congress while his son was a Marine fighting in Ramadi. Webb is himself the son of a Marine and a veteran of combat in Vietnam.
"It's harder having a son go to war than it is to go to war yourself, emotionally. The only time I ever saw my dad cry was when I said goodbye to him when I went to Vietnam."
"Did you cry when your son went to Iraq?" Martin asked.
"I shed more than one tear," said Webb.
Senator Webb's son is back home now. And Stephen Beck has a new job, one that does not require him to knock on doors.
But the fallen are still with him.
He visits their gravesites whenever he can and carries their photographs.
"I think the rest of my life I'm going to keep them foremost in my mind," Beck said.
"It doesn't go away. It doesn't get better," said Petraeus. "And you're always thinking about - especially at this time of year frankly - about families whose, whose soldier didn't return, who are celebrating holidays without them."
"It doesn't get better with time does it?" Martin asked Melissa Givens.
"No, it doesn't," she answered, "The bad days are still really bad."
"What makes it a bad day?"
"Right now? Christmas. Christmas sucks," she said with a sad laugh.
There are no happy endings to stories about the fallen. One young life has ended; other young lives have been blighted by grief. It takes all the families have just to survive.
"Did you think you could pull it off?" Martin asked Givens.
"Taking care of everything?" she asked.
"Become the person you've become?"
"No, I didn't," she answered. "I still kind of…I'm skeptical some days, you know? Every day I go wow, I did it. I did it another day. I'm good. I know he'd be proud of me."
The rest of us should ask ourselves if we've done anything to make the fallen proud.