Update 9:15 a.m., Feb. 24, 2018: This post has been changed to reflect subsequent news that President Trump's has now endorsed raising the minimum age for buying assault rifles from 18 to 21, and to reflect Sen. John Cornyn of Texas' pushback against that idea. -ML

America, we're on the brink of change when it comes to our extraordinarily lax gun culture, and the stakes couldn't be higher. Any false steps, and we'll lose this chance, and maybe for good.

We desperately need to find a way to make especially at-risk people work harder to buy, and in some cases to keep, especially lethal weapons. There is nothing in the Second Amendment that prevents this. And everything about the heart-wrenching regularity of school massacres like the Valentine's Day shooting in Parkland, Fla., says we must try.

It should be so simple. A 19-year-old with the history of violence and threats like Nikolas Cruz shouldn't have been able to buy an assault rifle. We ought to start with that simple premise and find common ground from there.

And yet, for years, elected officials, especially but not only Republicans, have refused to even talk about reasonable gun control. The moment they do, the radicalized National Rifle Association is all over the landscape shouting about freedom, tyranny, cold dead fingers and all the claptrap rest.

So that's why this moment, right now, is so remarkable. Chinks in that icy armor are forming in places that haven't seen a thaw in decades. In Austin, in Tallahassee and in Washington, Republican leaders are talking about gun control in a way that they haven't in a very long time. That's extraordinary.

Sen. John Cornyn of Texas wants to strengthen background checks in small but important ways. Right now, too few states report to the background database, and when they do, they share too little information. He wants that changed. Even the NRA, which has steadfastly argued for years background checks of any kind are useless and should not be expanded, supports this bipartisan baby step in the right direction.

Gov. Greg Abbott has ordered the Texas Rangers to call out school districts that haven't stepped up security plans in the wake of the Parkland shooting and the tragic church shooting in Sutherland Springs. It's not enough, but it's a start.

At the White House, President Donald Trump started off the week with a reasonable order to the Justice Department to propose a way to ban bump stocks, something lawmakers had said they'd consider after the Las Vegas shooting but so far haven't. He then wisely sat down with student protesters to hear them out. That's what presidents do, or should anyway.

Sen. Marco Rubio, R-Fla., cornered during a live town hall on CNN on Wednesday, defended his relationship with the National Rifle Association against fierce criticism and boos. He said reinstating the federal assault-rifle ban wouldn't work. But here's the thing: He also pledged to vote for raising the age required to buy rifles to 21, instead of 18. That's something Trump said on Friday he's support, too, though Sen. John Cornyn of Texas has been distressingly quick to push back on that idea as too much. Rubio's also on board with the better background checks and a bump stock ban.

If liberals can't see these steps, small as they are, as refreshing and even monumental developments, then they should look again. Of course the ideas don't go far enough, not given the enormous dimensions of America's problem with guns. When banning bump stocks — modifications that have been at play in one of the dozens of mass shootings that have rocked America — counts as reform, we know we are playing in the NRA's world.

But after years of an absolute freeze-out on the gun control debate, we're seeing a thaw. We need to celebrate it and nurture it. It can be snapped out as quickly as a late frost can choke out an early bud.

Already, the NRA has launched a full-scale counter attack.

NRA chief Wayne LaPierre at CPAC: “Evil walks among us and God help us if we don’t harden our schools and protect our kids.” https://t.co/n7TqA3VDnW pic.twitter.com/XNBVLdayxf — ABC News (@ABC) February 22, 2018

"They hate individual freedom," the group's chief executive Wayne LaPierre said Thursday to a packed house of conservatives at the annual CPAC convention. "They don't care about our school children. They want to make all of us less free."

There we have it again. The tyranny talk. Folks suggest making it harder for teenagers with histories to buy an assault rifle, and all the sudden we're talking about the survival of the Republic.

It's tempting to dismiss such prattle. Trouble is, it sure works. Trump was tweeting his fealty to the NRA by early Thursday and has doubled down on a line straight out of the NRA playbook. He said teachers with combat or police experience in their backgrounds should go to school heavily armed, ready to shoot it out with any would-be killer.

It's too early to tell whether the NRA's backlash will put the gun control debate back on ice. To my ears, there was a note of desperation in LaPierre's dark speech Thursday. The powerful images of these young students, their friends, teachers and coaches having been so senselessly murdered, have set the NRA atremble.

But it would be foolish not to believe the group's fear-based messages resonate. Last week, a reader wrote to tell me that he'd support reasonable gun control if he wasn't convinced it wasn't just a pretext for something more insidious.

"Nothing you propose in your recent piece is particularly horrifying to this patriotic Second Amendment advocate," he wrote. "The difficulty in negotiating sensible measures for making dangerous weapons less available to those who shouldn't have them is that, with leftists, it's never about what they say it's about."

In this case, he said, Democrats want to bring about "an eventual compete government monopoly of force, because without it they can't consolidate the tyranny they intend."

So when you consider what the students who are leading protests over guns are really up against, it's more than just the money and power of the NRA. What has really kept the politicians in the NRA's pockets all these years is the way the organization has spread fear and suspicion like fertilizer.

But for the first time in a generation, some of the most conservative figures in the land are peeking their heads out of those deep pockets and allowing that, perhaps, there might be a reform or two we could talk about that wouldn't mean the end of America.

That's progress. Some might call it the triumph of one kind of fear — the fear of more shootings —over another. But looking at the faces of the students who have mobilized since the latest shooting, I don't see fear, but anger and passion and participation.

And that makes me feel less afraid for our future.

Michael A. Lindenberger is a member of the Dallas Morning News editorial board. Email: mlindenberger@dallasnews.com

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