"Who would have ever thought, in America or anywhere in the world, that children would be slaughtered?" he asked. "It's changed me."
The debate is playing out not just in Newtown and Washington, but across the United States.
John Licata told CNN's iReport there needs to be better vetting before people buy guns, and assault weapons should be banned -- something Sen. Dianne Feinstein, D-California, says she'll propose once the new Congress convenes in January.
But some say the shooting illustrates the need for more armed guards -- and possibly armed teachers -- in schools.
Texas Gov. Rick Perry said that if school districts decide that arming teachers is the best way to keep schools safe, so be it.
If Texas residents are duly background-checked, trained and have a concealed handgun license, "you should be able to carry your handgun anywhere in the state," Perry said, according to CNN affiliate WFAA.
Gun owner Jameson Riley of Colorado said recent mass shootings have made him consider getting a concealed-weapon permit.
"I have a 2-year-old daughter, and she is the light of my life," Riley said. "And I would like to protect her."
Out of respect for the Newtown victims and their families, Dick's Sporting Goods has removed all guns from its store closest to Newtown, the company said.
Dick's, one of the largest sporting goods retailers in the world, also has suspended the sale of some semiautomatic rifles nationwide, the company said.
It was unclear how long Dick's will keep its suspension of "modern sporting rifles."
Two very premature funerals
While adults and children try to move on, two more 6-year-olds from Sandy Hook were being laid to rest Tuesday.
Jessica Rekos was obsessed with horses -- horse books, horse movies, drawing horses and writing stories about them. She was eagerly anticipating a pair of cowgirl boots for Christmas.
As her relatives grieve, they are also "trying to help her brother Travis understand why he can't play with his best friend," her family said.
James Mattioli liked to remind everyone that he was 6 and three-quarters. "He would often sing at the top of his lungs, and once asked, 'How old do I have to be to sing on a stage?'" his family wrote in an obituary.
In an online posting about his funeral, the Mattioli family called James "our beloved prince."
Also on Tuesday, the family of 6-year-old Charlotte Bacon planned to hold calling hours, or visitation.
Charlotte was a bundle of energy under her distinctive red curls. She also loved school and dresses, her grandmother told CNN affiliate WCCO in Minnesota.
Calling hours are also being held for 7-year-old Daniel Barden on Tuesday.
His "fearless" pursuit of happiness and life earned him two missing front teeth and ripped jeans, his family says. His mother described him as "just so good."
There are also calling hours Tuesday for Victoria "Vicki" Soto, a 27-year-old teacher who moved her students away from a classroom door when she heard gunfire. She was a hero, cousin James Wiltsie said.
The funerals will carry on for days. Some residents in this emotionally drained community plan to attend many this week.