Presidential candidate and former Texas Rep. Beto O'Rourke has talked tough about taking Americans' guns—but he's still not sure how he'd actually do it.

O'Rourke was confronted during the second hour of Tuesday's Democratic primary debate by debate moderator and CNN host Anderson Cooper about the candidate's promise to "take your AR-15" from last month's debate. In response, O'Rourke offered little in the way of substance.

Cooper pointed out that O'Rourke's campaign website calls for fining people who will not turn over their semiautomatic weapons—it is silent regarding the obvious follow-up question of how an O'Rourke administration would know which households to fine, but we'll leave that aside for now. "That doesn't take those weapons off the street," said Cooper. "So, to be clear, exactly how are you going to take away weapons from people who do not want to give them up, and you don't know where they are?"

O'Rourke's response? If someone refuses to turn in their semiautomatic rifles, "or brings it out in public and brandishes it in an attempt to intimidate—as we saw when we were at Kent State recently—then that weapon will be taken from them."

"If they persist, there will be other consequences from law enforcement," he said, before adding that he expects Americans will "do the right thing" and follow these laws. "We don't go door-to-door for any other laws in this country, we're not doing it here," said O'Rourke.

A couple of things about that.

First of all, if he's going to continue invoking Kent State in his gun control screeds, someone really ought to tell O'Rourke who did the shooting in the infamous Kent State massacre. Spoiler alert: it wasn't the law-abiding American citizens practicing their constitutional rights.

Second, all this stuff about Americans "doing the right thing" and following the law is nonsense. There's no obligation to obey an obviously unconstitutional gun grab. As a practical matter, history suggests most people won't.

When New Jersey implemented a mandatory gun buyback program in the early 1990s, the state obtained a mere 18 guns of the estimated 100,000 to 300,000 firearms owned by Garden State residents—and only four were turned over voluntarily. Australia's much ballyhooed gun buyback program netted between 650,000 and 1 million firearms, about a quarter of the estimated number of guns owned by Australians at time. It is estimated that there are more than 350 million privately owned guns in the United States. Taking the rest would require a massive mobilization of federal, state, and local law enforcement.

Third, this is a long, long way from "Hell, yes, we're going to take your guns." And maybe that's a good thing. Maybe that's a signal that O'Rourke realizes he's not going to be able to order law enforcement officers to go door-to-door to strip people of their Second Amendment rights.

But this reveals something else about O'Rourke's promises to seize Americans' guns: This was never a realistic policy that could actually be implemented—or even passed by Congress. As Reason's Jacob Sullum wrote last month, "vicious scapegoating is the whole point" of O'Rourke's gun grab.

After Tuesday's debate, that seems more clear than ever.

But one of the consequences of O'Rourke's fixation on gun takings is that it's created space for other candidates to stake out other outlandish positions that seem downright reasonable by comparison. On Tuesday night, both Mayor Pete Buttigieg and Sen. Elizabeth Warren (D–Mass.) spoke favorably about passing an "assault weapons ban" if elected.

"We are this close to an assault weapons ban. That would be huge," said Buttigieg.

Would it? America had an assault weapons ban from 1994 through 2003, and it didn't have any effect on the number of gun homicides in the country. There are probably a few reasons for that—identifying guns as "assault weapons" is an imprecise science, one that's based largely on cosmetic details. More importantly, most gun homicides in America are committed with handguns—not AR-15s or AK-47s.

O'Rourke doesn't know exactly how he's going to remove guns from American streets—but that's okay, because gun homicides are on the decline anyway.

O'Rourke can't acknowledge that reality or many of the other basic realities of the gun debate. Instead, he's left with tough talk and not much else.