The US Constitution's Second Amendment protects the right to bear arms.
Wayne, our President says you're a great American patriot.
The responses from businesses come as gun control activists and social media users continued to increase pressure on lawmakers and industry players to take action in response to the shooting at Marjory Stoneman Douglas HIgh School. Numerous teenagers and their parents taking part have called for more curbs on guns. "The NRA wants to do the right thing", Trump said.
Appearing to throw his weight behind Mr Trump's suggestion that teachers should be able to defend themselves and their pupils in such an event, he said: "We must immediately harden our schools".
Schools are designated as "gun-free zones", he continued, leaving them as "wide open targets for any insane madman bent on evil to come there first".
"We share a goal of safe schools, safe neighborhoods, and a safe country", LaPierre said.
He also called out leading Democrats by name, denouncing Senators Elizabeth Warren, Bernie Sanders and others as "European-style socialists".
"You should be anxious and you should be frightened" about the potential of another Democratic takeover of the House, Senate and White House", he said.
"Anyone who pushes arming teachers doesn't understand teachers and doesn't understand our schools". Opinion polls indicate Democrats generally favor more restrictions on guns while Republicans oppose them.
US companies that have partnered with the National Rifle Association to offer discounts and benefits to its members have begun to distance themselves from the gun lobbying group after the latest school shooting.
The NRA has not commented on the announcements.
The notion of arming teachers at USA public schools, which are largely governed by states, local councils and school boards, has been raised by some politicians in the past but has been dismissed by many critics as fraught with danger.
A White House official told CNN that Trump spoke with NRA executive director Chris Cox.
Controversy surrounding guns and gun violence has reached new heights since another mass shooting last week. Such devices were not used in the Florida shooting.
Indeed, it is not clear that the GOP-controlled Congress, which is in recess, will take up or act on a variety of legislative proposals that have been made to address gun violence.
The left-leaning news site, ThinkProgress, said it rounded up a list of 22 corporations it said was "making membership to America's premier gun-lobbying group more enticing" by offering such discounts and promotions.
"We focus on engaging with the company and understanding how they are responding to society's expectations of them", BlackRock spokesperson Ed Sweeney told Reuters. Cameron Kasky, a 17-year-old who survived the Parkland shooting, asked Rubio amid loud cheers.
The current federal minimum for buying handguns from registered dealers is 21, but the requirement in most places is 18 for rifles, including assault-type weapons such as the AR-15.