"Ma," he told Theresa Ricks in one of their many long-distance conversations over the past nine months, "I achieved a whole lot in my life, didn't I? I finished high school, I got married, I had a baby and I went into the service. I filled up the list of things to do. I'm proud of myself."
But in an instant last Sunday, someone with a gun - not a Taliban insurgent in an Afghan village, but some as-yet-identified killer in Baltimore - put an end to all that.
Home on leave for the holidays, Williams was shot to death in his sport utility vehicle as he drove back from grocery shopping in Southwest Baltimore. Police still have no suspects and know of no reason for the shooting.
Saturday, on what would have been Williams' birthday, his family and friends gathered to release 23 balloons - one for each year of his life - and to deal with the tragic irony of an American soldier, back from a war zone 7,000 miles away, dying violently on the streets of his hometown.
The way his family tells it, here was a young man who indeed had reason to be proud. He was beating the odds, through hard work and a sense of responsibility.
His sister, Katrice Lambirth, said Williams didn't have time for sports during his years at Edmondson Westside High School because he had jobs, working in food services at the Charlestown retirement community in Catonsville and at a McDonald's on Caton Avenue. Williams eventually became one of the managers at the fast-food restaurant, but he yearned to do more.
That's when the idea of joining the Army came up. It seemed like the best idea at the time, and it was something a lot of young Americans did - in record numbers, according to the Pentagon - as they faced recession and a bleak job market in 2008.
Williams - his mother called him Clifford, his little sister called him Mar-Mar and his friends called him Jamar or Lucky - volunteered for the Army in February of last year, the same month he married Angel Webster, the mother of his child.
It wasn't long before Williams was in basic training.
"He wanted a better life for his wife and child," Lambirth said. "He wanted more for them."
He thought a military career might provide it.
"I thought he was joking when he told me he was going into the Army," said his mother. "I said, 'Clifford are you sure that's what you want to do?' And he said, 'Yeah, there are no jobs out here. I can't support my family. I need a decent job.' That day the man from the Army came and took him away - that hurt, and I've been praying for him every day since then."
After basic training, Williams received special instruction in helicopter mechanics. He was assigned to an aviation unit of the 82 Airborne, at Fort Bragg, N.C. He went to Afghanistan last April.
"He called me all the time, every chance he could," his mother said. "When he called, that made my day. One day, we got disconnected all of a sudden, and when he called back, he said, 'That might have been a bomb.' And I worried about him, but he said to me, 'Ma, I work on the helicopters,' and I said it didn't matter because anything could happen over there. I prayed and prayed that my baby would just do his time over there and come home."
Ricks said one day she and her son spoke on the phone about the crime in her neighborhood and the violence that's given Baltimore an international reputation. He was concerned about his family and the kind of environment in which his young son would grow up.
"Ma," she remembers him saying, "I'm here - we're over here - fighting for them and they're back there hurting our own people?"
Ten days ago, the phone rang in Theresa Ricks' rowhouse at 1 a.m. "Who is this calling me?" Ricks asked, then promptly hung up without waiting for an answer.
"Oh, my goodness," she realized in the next instant, "that could have been my baby!"
Then she heard tapping on her window. She opened the door to find her son standing there, smiling, his arrival a week before Christmas a well-executed surprise.
"I said, 'Thank you, God.' All I ever wanted was God to bring my baby back home for the holidays."
Williams was supposed to attend his little sister Tionna's holiday concert at her elementary school on Wednesday. He had promised to take his mother shopping, too. But then the phone rang with the news that Williams had been shot to death.
"This can't be happening," Theresa Ricks remembers saying out loud. "This can't be happening to my baby. I just saw him. He was supposed to take me shopping. ... He went over there [Afghanistan] to fight for us, and someone here is going to take his life? Don't tell me that."
The funeral will be held Wednesday.
On Saturday afternoon, relatives and friends, many of them wearing new white T-shirts bearing Williams' Army photograph, gathered at Ricks' modest rowhouse facing Green Mount Cemetery in East Baltimore. She fixed the birthday meal her son would have wanted - chitterlings, collard greens and shrimp fried rice - as if she expected him to be at her door again.
Then she and the others went outside into the drizzle at dusk, and they called out, "Happy birthday, Jamar" three times, then released the balloons, which floated over the cemetery and disappeared in minutes into the fog.