On 9 March, Florida responded to high school protests by swiftly enacting a package of mostly-sensible gun control measures. This, despite a culture so gun-friendly that it’s sometimes called the ‘Gunshine State’. To the applause of gun control advocates, Florida banned devices that turn semi-automatic weapons into machine guns, raised the minimum age for buying long guns to 21, and empowered courts to disarm individuals who are shown to pose an ‘extreme risk.’ To the alarm of gun control advocates, it also gave local officials the discretion to arm school personnel, in a solution embraced by President Trump and the National Rifle Association (NRA).

Of course, Florida’s law is incomplete, and arming teachers would be the height of folly, says Chelsea Parsons, Vice President, Gun Violence Prevention at the Center for American Progress. ‘But, the biggest point I'd make is that it happened – that the“Gunshine State” debated and quickly passed a gun control package, and it was signed into law by a Republican governor who was rated A+ by the NRA. That in and of itself speaks to tremendousprogress, and frankly speaks to the tremendous power of these students.’

Nevertheless, gun makers have little to fear from litigation, because in 2005 Congress gave them near total immunity. But, reinforcing the shift in state politics is a changed investment climate. Share prices in the US gun industry usually rise after mass shootings (because sales spike), but this time they fell.The fund giant Blackrock talked gun safety with two leading gun makers. Dick’s Sporting Goods ended assault weapon sales after a pressure campaign by the Interfaith Center for Corporate Responsibility.

At the same time, guns demand a federal solution, because they cross state and national borders. America’s gun murder rate is 25 times higher than in peer nations, according to a new American Journal of Medicine study. What’s more, Parsons recently found, America produces 70 percent of the crime guns seized in Mexico, which suffers grievous gun violence despite reasonably tight gun laws. The President’s border rhetoric overlooks how the export of violence goes in the other direction, says Parsons. Unfortunately, at the federal level, the post-Parkland progress of the gun debate has been halting.

Appearing live on television at the end of February, President Trump surprisingly embraced universal background checks and an assault weapons ban, a pair of policies that top the wish list of gun control experts. There was widespread scepticism given the President’s friendship with the NRA, and his reversal last year of an Obama executive order to bar the mentally ill from buying guns.

After two weeks of pressure, the President abandoned his vows on assault weapons and background checks on 12 March, as well as his commitment to raise the federal age limit for buying long guns. ‘Not much political support (to put it mildly),’ he said of the age policy on Twitter.

Although the President might be correct if one defines political support as support in Congress, over 80% of the public favors raising the age limit, according to a new Politico/Morning Consult poll. Universal background checks command near-universal support, as does the ban on selling guns to the mentally ill that the President rescinded last year. ‘The gun lobby has shown how damaged our democracy is,’ says the gun regulation researcher John Donohue of Stanford Law School. ‘If you look at public opinion polls, 93 percent of gun owners believe you should have universal background checks – and the federal government won’t even put that to a vote.’

Still, Parkland has shifted the debate even at the federal level. The President now supports a bill toimprove background checks by forcing other federal agencies to share their records with the FBI. He also urges states to empower their courts to issue ‘extreme risk protection orders,’ as Florida has done.Meanwhile, an aggressively gun-friendly bill that passed the House in December may be stalling. The gun lobby wishes to force ‘gun-control states’ to let visitors from ‘gun-rights states’ carry concealed weapons. After Parkland, 60 Senators are less apt to make ‘conceal carry’ a national policy.

Parkland poses a sharp contrast with the 2012 shooting at Sandy Hook High School, which inspired Republican state legislatures to pass seventy laws that only expanded gun rights. Even more disturbing, a recent Science study found that Sandy Hook inspired the purchase of 3 million extra guns in the next five months – and that led to the deaths of 20 children beyond the 20 killed at Sandy Hook. ‘The more guns there are to handle the more likely something will go wrong,’ says Stanford Law’s Donohue. ‘That’s the iron law of gun policy.’

Donohue thinks this moment is different because the past six months have seen three of history’s worst mass shootings: in Parkland, Las Vegas and Sutherland Springs, Texas. He also cites the galvanising of dissent in Trump’s America - and the new energy of youth protests.

‘After these big shootings there's a cycle that we go through, and there’s a dance that happens,’ says Parsons. ‘It’s the outrage and then it’s “thoughts and prayers” and then it’s calls for action and then critiques of calls for action and then it plays itself out in a couple of days. What has happened this time, because of the advocacy of the students from Parkland, is that we have extended the life of this conversation. So we're still talking about gun violence a month after that shooting. I think that is directly credited to the students…. From the moment this happened, they stood up and said, “No more.”’