(CNN) Beto O'Rourke's best moment on Thursday's Democratic presidential debate -- which also doubled as his best moment in the 2020 campaign to date -- came when ABC's David Muir asked whether he supported a mandatory buyback of assault weapons.

"Hell, yes, we're going to take your AR-15, your AK-47," O'Rourke said to raucous applause from the crowd in Houston, Texas. "We're not going to allow it to be used against our fellow Americans anymore."

The former Texas congressman defended that stance in an interview on CNN's "New Day" Friday, insisting the issue would not hurt his party.

"It's not a concern of mine and that's in part informed by listening to people in conservative parts of America," he said. "And folks are saying, 'Look, I would give up that AR-15 or that AK-47. I don't need it to hunt, don't need it to defend myself in my home.' They recognize this is a weapon designed for war, to kill people as effectively, as efficiently, and in a great a number as possible."

Which, well, count me skeptical that O'Rourke's idea will gain widespread political support. Here's why.

For decades, the National Rifle Association -- and its Republican allies in Congress and now in the White House -- have used the idea of confiscation to win the gun debate. If Democrats were in control, they'd come to your house and take your guns!, the argument goes. It's why gun purchases soared in the immediate aftermath of Barack Obama's election in 2008, for example.

"It depends on if Democrats want to take your guns away," President Donald Trump said in response to questions Thursday about whether some sort of gun control measure might be passed by Congress this fall. "If this is a movement by the Democrats to take your guns away, it's never going to happen."

Up until very recently, the Democrats-want-to-get-rid-of-the-Second-Amendment talk was, like so much of Trump's rhetoric, outlandish and without any basis in facts. Obama in 2008 and 2012 and Hillary Clinton in 2016 expressly made clear they had no interest in any sort of mandatory collection or buyback program.

"Of course Hillary does not support national mandatory gun buyback programs, including those modeled after Australia's program," said a Clinton campaign spokesman in 2016 when the NRA attacked her for allegedly supporting confiscation. "She was discussing voluntary buyback programs, which are drastically different than what occurred in Australia and are regularly run by cities across the America."

That changed -- or at least shifted -- on Thursday night with O'Rourke's comment.

While a mandatory buyback campaign of weapons like the AR-15 and AK-47 doesn't amount to a wholesale gun confiscation, it walks much closer to that doomsday scenario the NRA has spent years painting as just over the horizon if Democrats get into power.

Even if O'Rourke never even sniffs the Democratic presidential nomination, the eventual nominee will have to answer for his support of a mandatory buyback program.

And whether or not O'Rourke is the nominee, Republicans will use his comments to stoke fear and anger in their base -- see, we told you Democrats really want to take all your guns ... just look at this quote from Beto O'Rourke!!!

Is it possible that the debate on guns and gun control has been changed in a fundamental way by the recent spate of mass shootings? O'Rourke seems to believe it has. And maybe it has! But if it hasn't, then O'Rourke just handed Republicans a massive political gift: A club to bash the eventual Democratic nominee with on confiscating peoples' guns.