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TOPSHOT - Marjory Stoneman Douglas High School staff, teachers and students return to school greeted by police and well wishers in Parkland, Florida on February 28, 2018. 
Students grieving for slain classmates prepared for an emotional return Wednesday to their Florida high school, where a mass shooting shocked the nation and led teen survivors to spur a growing movement to tighten America's gun laws. The community of Parkland, Florida, where residents were plunged into tragedy two weeks ago, steeled itself for the resumption of classes at Marjory Stoneman Douglas High School, where nearby flower-draped memorials and 17 white crosses pay tribute to the 14 students and three staff members who were murdered by a former student.
 / AFP PHOTO / RHONA WISE        (Photo credit should read RHONA WISE/AFP/Getty Images)
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TOPSHOT - Marjory Stoneman Douglas High School staff, teachers and students return to school greeted by police and well wishers in Parkland, Florida on February 28, 2018. Students grieving for slain classmates prepared for an emotional return Wednesday to their Florida high school, where a mass shooting shocked the nation and led teen survivors to spur a growing movement to tighten America's gun laws. The community of Parkland, Florida, where residents were plunged into tragedy two weeks ago, steeled itself for the resumption of classes at Marjory Stoneman Douglas High School, where nearby flower-draped memorials and 17 white crosses pay tribute to the 14 students and three staff members who were murdered by a former student. / AFP PHOTO / RHONA WISE (Photo credit should read RHONA WISE/AFP/Getty Images)
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This image made available by the Broward County Sheriff's Office on Sunday, Feb. 18, 2018, shows Sheriff Scott Israel, holding the hand of Anthony Borges, 15, a student at Marjory Stoneman Douglas High School. The teenager was shot five times during the massacre on Valentine's Day that killed 17 students. Borges is being credited with saving the lives of at least 20 other students. (Broward County Sheriff's Office via AP)
Broward County Sheriff's Office via AP
This image made available by the Broward County Sheriff's Office on Sunday, Feb. 18, 2018, shows Sheriff Scott Israel, holding the hand of Anthony Borges, 15, a student at Marjory Stoneman Douglas High School. The teenager was shot five times during the massacre on Valentine's Day that killed 17 students. Borges is being credited with saving the lives of at least 20 other students. (Broward County Sheriff's Office via AP)
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Correction: This story has been updated to correct the day on which Trump spoke.

(CNN) —  

The President had three things to say on Twitter about the Parkland school shooting in the 18 hours after it occurred.

First, condolences for the victims and a lament that no child or teacher should feel unsafe at school. Second, assurance that the federal government would work with authorities in Florida and the governor there. Third, blame that there were clues missed as to the shooter’s mental fitness and his ability to legally buy the AR-15 used to go on the rampage.

Here’s that third tweet, offered at 7:12 a.m., ET on Thursday, less than 24 hours after the shooting: “So many signs that the Florida shooter was mentally disturbed, even expelled from school for bad and erratic behavior. Neighbors and classmates knew he was a big problem. Must always report such instances to authorities, again and again!”

What Trump doesn’t mention is what exactly he and his administration will do about gun violence or about school shootings, which feel like an epidemic.

After other recent shootings, including the one that killed more than 50 people attending an open air concert in Las Vegas last fall, he promised that there would be a time to talk about gun regulations.

That time has not yet come.

But there is one important thing Trump has done on the issue of gun control during his time in office.

A little less than a year ago, on February 28, 2017, he signed a measure nixing a regulation aimed at keeping guns out of the hands of some severely mentally ill people. It’s critical to note that it’s not at all clear it would have applied to the shooters in Florida nor Las Vegas, and there’s no reason to believe it would have stopped the massacre.

Read the full bill text here.

Here’s the description of that rule CNN published last year in a story by Ted Barrett and Deirdre Walsh:

The regulation, finalized in December under Obama’s tenure, required the Social Security Administration to disclose information quarterly to the national gun background check system about certain people with mental illness.

While the list of eligible mental disorders is long – ranging from anxiety to eating disorders to schizophrenia – those who would have been reported by the agency had to meet two main criteria: a) They were receiving full disability benefits because of a mental illness and couldn’t work and b) they were unable to manage their own benefits, thus needing the help of a third party to do so.

It’s also not clear – and perhaps unlikely – that the man accused of terrorizing the high school in Parkland and killing 17 people there would have met either of the criteria laid out to be reported under that rule.

What’s more, the rule Trump rescinded was opposed by both the American Civil Liberties Union and the National Rifle Association, so it wasn’t exactly universally hailed.

Related: Gun lobbyist helped write ATF official’s proposal to deregulate

But it’s also true that it was a rule aimed at keeping guns out of the hands of the mentally ill. And almost the first thing the President did after this most recent shooting was to complain that the shooter’s mental illness hadn’t been reported.

Trump was clear in his first spoken remarks, broadcast from the White House before noon Thursday, that any action must actually be effective.

“It is not enough to simply take actions that make us feel like we are making a difference. We must actually make that difference,” he said.

There is no panacea piece of legislation to keep guns out of the hands of just the people who would go on a murderous spree. The shooters in mass shootings seem to share the problem of being troubled, but the clues missed by those around them are different. In the coming days and weeks, we’ll learn why this one slipped through the cracks.

But the laws in this country continue to move in the other direction – away from regulation. New York magazine documented the ways in which they believe the Trump administration and Congress have actually tried to make it easier for certain groups to buy guns over the past year. It’s a not insignificant amount.

One of those ways is that in Trump’s budget, on page 719, as HuffPost points out, the White House suggests cutting $12 million from the federal program that helps states maintain the background check system.

The White House budget is unlikely to become law, but it is important as a statement of priorities.

Related: Why Congress is hesitant to pass gun control, by the numbers

And priorities are key in the gun debate, or lack thereof. CNN’s Harry Enten wrote Wednesday that you shouldn’t expect much from Congress in the wake of this (or any) shooting since the issue of guns is one of the most polarizing and misunderstood.

The priorities are clear that it’s not likely any gun legislation is going to pass the House or the Senate, and it’s unlikely Trump will propose anything new.

CNN’s Jenny Hansler contributed to this report.