Trump has previously cited mental health issues, not guns, as the biggest cause of shootings in the U.S. But his comments on Saturday are his most extensive and emotionally charged about firearms since he launched his campaign in June, as he spoke about his personal gun ownership and elicited his biggest applause of the afternoon in discussing gun rights.
"By the way, it was a gun-free zone," he said at a campaign event in Franklin, Tennessee. "Let me tell you, if you had a couple teachers with guns in that room, you would have been a hell of a lot better off."
Trump went on to say he has a license to carry a gun in New York, and if someone attacks him, he will respond.
"In fact, I have a license to carry in New York, can you believe that? Nobody knows that," he said.
"Can you imagine? Somebody says, 'There's Trump, he's easy pickings.' What'd you'd say?" Trump said, mimicking holding a gun with his hand.
Nine people were killed and nine others were injured in Thursday's shooting. Law enforcement officials on Saturday said Chris Harper-Mercer, the shooter behind the deadly rampage, killed himself after exchanging gunfire with authorities
Trump's suggestion for an armed presence on school grounds isn't new. In the aftermath of the Newtown, Connecticut, school shooting in 2012, National Rifle Association Executive Vice President Wayne LaPierre called for armed security at schools across America.
A strong gun-rights advocate
Trump came out as a strong gun-rights supporter in a position paper he released last month.
"The Second Amendment to our Constitution is clear. The right of the people to keep and bear Arms shall not be infringed upon. Period," he said.
Trump then recommended expanding the right to carry.
"The right of self-defense doesn't stop at the end of your driveway. That's why I have a concealed carry permit and why tens of millions of Americans do too. That permit should be valid in all 50 states," he wrote.
In July, Trump also called for an end to gun-free zones
in the wake of the shooting in Chattanooga, Tennessee, that left four Marines and one sailor dead.
But the day after Thursday's massacre, Trump said if he became president
, he doesn't expect to halt all mass shootings because there will always be people that society can't stop.
"You're going to have these things happen and it's a horrible thing to behold, horrible," Trump said on MSNBC's "Morning Joe."
"It's not politically correct to say that, but you're going to have difficulty and that will be for the next million years, there's going to be difficulty and people are going to slip through the cracks," Trump added. "What are you going to do, institutionalize everybody?"
Those comments echo ones he made shortly after two journalists were shot to death on live television in August, when he said he was in favor of addressing mental health issues to prevent future tragedies.
"This isn't a gun problem, this is a mental problem," Trump told CNN's Chris Cuomo on "New Day."
"It's not a question of the laws, it's really the people."