(CNN) Beto O'Rourke did something new for a major Democratic presidential candidate at Thursday night's debate when he said, very clearly and without any prevarication, that he'd take "weapons of war" and certain guns away from law-abiding Americans.

"Hell, yes, we're going to take your AR-15, your AK-47. We're not going to allow it to be used against our fellow Americans anymore," said O'Rourke, a former congressman from El Paso, Texas, who has re-created his presidential campaign around the issue of gun control after a mass shooting last month in his hometown.

O'Rourke is one of three Democrats, along with Sens. Kamala Harris of California and Cory Booker of New Jersey to support mandatory buybacks for certain guns. Other Democrats would make them illegal but not require them to be bought back by the government. That was O'Rourke's position, too, until the shooting in El Paso.

At the debate, O'Rourke had been asked whether he was ready to take guns away from people. He said yes, "if it's a weapon designed to kill people on a battlefield, if the high-impact, high-velocity round, when it hits your body, shreds everything inside of your body because it was designed to do that so you would bleed to death on a battlefield and not be able to get up and kill one of our soldiers."

This is something of a turning point for Democrats.

And while several other Democratic candidates complimented O'Rourke for his activism on gun control after the El Paso shooting, none of them endorsed his proposal for mandatory buybacks for certain guns.

O'Rourke has explained his plan before, as he did to CNN's Dana Bash earlier this month. She asked him if such a buyback plan would seem like confiscation and if so, galvanize gun rights activists.

"You know, more than I worry about the politics or the polling, more than I care about what the NRA has to say on this, I care for my kids, and this country, and people who live in terror every day, people in El Paso, Mexican Americans who say: 'I feel like I have a target on my back. I'm afraid to go out in public,' " he said.

Republicans have been warning for decades that Democrats will try to take weapons away from gun owners. Donald Trump said that about Hillary Clinton in 2016. John McCain said that, somewhat jokingly, about Barack Obama in 2008. The National Rifle Association was not joking at all when it said the same thing. Dick Cheney said that about John Kerry in 2004. Kerry was so nervous about turning off gun lovers that he was be photographed on a hunting trip to make people feel at ease.

That kind of pandering is no more. O'Rourke went to a gun show earlier this year and then endorsed a national gun licensing program like the one the NRA has long warned against.

In fact, earlier Thursday, President Trump said a new push for some kinds of tweaks to the background check system could happen only if Democrats don't try to take guns away from people.

"It depends on whether or not the Democrats want to take your guns away, because there's a possibility that this is just a ploy to take your guns away or whether or not it's meaningful," he told reporters at the White House. "If it's meaningful we'll make a deal. If this is movement by the Democrats to take your guns away, then it's never going to happen because we're never going to let that happen. We will always be there for our Second Amendment."

Democratic presidential candidates and presidents have been arguing, during that whole time, that they absolutely would not. But then adding that they want to enact new gun control measures.

Obama complained in 2008 that certain voters clung to their guns and religion, but he also made clear he respected the Second Amendment.

Hillary Clinton said something similar that same year.

"I respect the Second Amendment," she said. "I respect the rights of lawful gun owners to own guns, to use their guns. But I also believe that most lawful gun owners whom I have spoken with for many years across our country also want to be sure that we keep those guns out of the wrong hands. And as president, I will work to try to bridge this divide, which I think has been polarizing and, frankly, doesn't reflect the common sense of the American people."

Obama appeared at a town hall about guns on CNN in 2016 and was asked by Anderson Cooper what he'd say to someone who was afraid he wanted to take guns. Obama pointed out he'd been President for years by that point and a lot of people were still buying guns.

"What I've said consistently throughout my presidency is I respect the Second Amendment; I respect the right to bear arms. I respect people who want a gun for self-protection, for hunting, for sportsmanship."

But he also argued forcefully for new gun control measures, although they all fell short of a mandatory buyback program like the one O'Rourke is proposing.

That kind of language, trying to allay fears of Second Amendment supporters while calling for new restrictions, is gone at least with O'Rourke, who has had enough with certain guns.