"Arming teachers is inane and insane - a sure path to reckless and panicky shooting, gun theft, and other deadly dangers. If they truly cared, they would protect them".
LaPierre also made a populist appeal by painting people who want common-sense gun control as either out-of-touch elites or socialists.
"The NRA does care", he told the gathering at the Gaylord National Resort and Convention Center in National Harbor, Maryland. Surveillance video of the school shooting in Florida last week showed that resource officer Scot Peterson, tasked with school security, took up position behind a cement column outside the school after gunman Nikolas Cruz began shooting and did not go in to challenge him for the six minutes during which he carried out the carnage, county authorities in Florida revealed.
None of the companies gave details about why or when they chose to cut ties with the NRA, but the news comes as the hashtag #BoycottNRA has taken social media by storm.
"Can we protect so much with armed security, while we drop our kids off at school, that are so-called gun-free zones, that are wide-open targets for any insane madman bent on evil to come there first?" "And evil must be confronted immediately with all necessary force to protect our kids".
But Randi Weingarten, president of the 1.7 million-member American Federation of Teachers union, disagreed.
Trump's morning tweet was part of a longer thread of posts in which Trump outlined potential gun control policies, his response to the mass shooting at Marjory Stoneman Douglas High School in Florida.
"Let teachers teach", NYPD Commissioner James O'Neill said Friday following a breakfast at New York Law School where he was the keynote speaker.
The head of the biggest gun lobby in the USA has accused Democrats of pushing a "socialist" agenda to deprive gun owners of their weapons, in an uncompromising speech just a week after 17 people died in the Florida school shooting. "We give them a little bit of a bonus". Marco Rubio, who has an A+ rating from the NRA, announced he was opposed to arming teachers and was in favor of raising the age limit from 18 to 21 on individuals purchasing semi-automatic weapons like the AR-15.
LaPierre said his organization has the best interests of the nations' students and teachers at heart in the call to arm school staffers adding, "to stop a bad guy with a gun, it takes a good guy with a gun".
Mr Trump also said on Thursday he would push for national background checks for persons with mental health issues, which Mr LaPierre later echoed at the conference. Trump also said he supports efforts to improve the federal background system.
It's not just First National Bank of Omaha that's being pressured to end its relationship with the country's most powerful gun lobby. The availability of military assault rifles to any individual who can pay for them has been a prime factor in the appalling number of mass shootings in America. "Do mommy and daddy own a gun?" he said. Since then, survivors of the shooting have joined with students across the country to press for tougher gun laws. The NRA often prefers to stay out of the media spotlight in the wake of a major shooting.