The National Rifle Association (NRA) has been influencing the US gun control debate for decades.
As the US grapples with its 18th school shooting since January 1, gun control measures are once again front-and-centre.
But what is the National Rifle Association (NRA) and how much power does it have in influencing the gun control debate?
How did the NRA begin?
According to the organisation's website, the NRA was established in 1871 to "promote and encourage rifle shooting" by veterans of the US civil war.
"Dismayed by the lack of marksmanship shown by their troops, Union veterans Col. William C. Church and Gen. George Wingate formed the National Rifle Association," the website says.
The organisation went on to "promote the shooting sports among America's youth" early last century by urging the establishment of rifle clubs at all major colleges and universities.
The NRA started being a political player in 1934 when it began mailing out legislative "facts and analyses" to members.
Then in 1975, "recognising the critical need for political defense of the Second Amendment" - or the constitutional right of the people to keep and bear arms - it formed the Institute for Legislative Action. With that, the NRA started to directly influence policy around guns.
What is the NRA today?
Since 1975, the NRA has grown into a major force in US politics, with its lobbying arm "working vigorously to pass pro-gun reform legislation".
The University of Sydney's Philip Alpers is the founding director of gunpolicy.org. He told SBS News "the NRA is regularly voted by a poll of Congressional representatives in Washington, DC as America's most influential lobby group. That is, above Big Oil, Big Pharma".
"At present, the NRA has total control over gun policy in the USA. This will change only when a large majority of Americans reject the NRA's ideas. That is, not in our lifetimes."
The association has 5 million official members and as many as 17 million Americans identify themselves as members of the NRA, experts told SBS.
It has an annual budget of $250 million dollars and between 2000 and 2010 it spent 15 times as much on campaign contributions as gun control advocates.
International law expert, Professor Clive Williams told SBS News that the NRA "has considerable political lobbying power through its support of pro-gun congressmen and women and opposition to anyone who is pro-gun control".
For example, the NRA publicly grades politicians from A to F on their attitudes on gun rights.
And gun control groups point to efforts like these as the biggest roadblocks in meaningful gun control measure being passed in the US.
Everytown for Gun Safety and Moms Demand Action for Gun Sense in America recently took out a two-page ad in the New York Times listing 100 US politicians who have accepted donations from the NRA.
Moms Demand Action for Gun Sense in America founder Shannon Watts said that politicians who don't take action to stop gun violence are "complicit in the deaths of our children".
The NRA has also been getting more creative with recent lobbying efforts, such as starting NRATV - a media arm of the organisation.
But Everytown for Gun Safety said NRATV "promotes dangerous conspiracy theories, racially charged rhetoric, and violent demonisation of the NRA's political opponents".
What is the relationship between Trump and the NRA?
Trump is a member of the NRA and received $30 million from the organisation to support his presidential campaign.
Since assuming the presidency, Trump has publicly stood up for the NRA, even in the aftermath of gun violence.
"There is no bigger fan of the Second Amendment than me and no bigger fan of the NRA," Trump said in the aftermath of the Parkland, Florida high school shooting.
"What many people don't understand, or don't want to understand, is that (NRA leaders) Wayne, Chris and the folks who work so hard at the @NRA are Great People and Great American Patriots. They love our Country and will do the right thing. MAKE AMERICA GREAT AGAIN!," he recently tweeted.
However, Trump has also indicated a willingness to embrace some gun control measures and has urged politicians not to be "afraid" of challenging the NRA.
Will the recent Florida shooting change NRA activities?
US airlines Delta and United on Saturday joined a growing list of companies cutting ties with the NRA in the wake of the high school shooting in Florida.
In response, NRA chief Wayne LaPierre slammed what he called "the shameful politicisation of tragedy," and called for Americans to be the first line of defense - meaning arming teachers.
US policy analysts told SBS News the recent events will not change the NRA's overall aim and tactic.
Professor Clive Williams said the NRA "may back off politically on some issues such as bump stocks but will resist any attempt to raise the age for gun ownership".
Associate Professor Tim Lynch from the University of Melbourne told SBS News "their defenders see a slippery slope. If we allow them to ban these types of guns the government will eventually ban all guns".
"They play extraordinarily well to a US political tradition which is distrustful of federal government power."
Additional reporting: AFP