Three days after the massacre that left 17 dead at Marjory Stoneman Douglas High School, the rift between the pro and anti-gun camps in southern Florida may as well be a canyon.

Cars packed into the fields on the Miami-Dade Fairgrounds on Saturday, where the Miami Gun Show was being held – an event that was went forward in spite of the shooting days earlier that has left the surrounding communities reeling with pain. Attendees had their pick of handguns, shotguns, and semi-automatic rifles; the very kind of gun that has once again been used for mass murder.

Just an hours’ drive north, people packed into a courtyard outside the US District Court for the Southern District of Florida in Fort Lauderdale, and spilled over onto a terraced water fountain that had been dried up. In the centre of the crowd, high school students from Stoneman said enough is enough, grieving parents promised their children's lives were not lost in vain, and politicians promised allegiance to the cause – all to thunderous applause that bounced off the cement walls and overhangs.

"We are going to be the last mass shooting," Emma Gonzalez, 17, a Parkland student who survived the shooting, told the crowd. "We are going to change the law. That's going to be Marjory Stoneman Douglas in that textbook, and it's all going to be due to the tireless efforts of the school board, the faculty members, the family members and most importantly the students."

In the aftermath of the high school shooting in Parkland, the debate on how to stem the epidemic of gun deaths in America has been given new life. President Donald Trump and other Republicans have argued that the issue is one of mental health – only unstable individuals are going to turn a gun on a hallway full of high school students, they reason.

Florida shooting – in pictures Show all 10 1 /10 Florida shooting – in pictures Florida shooting – in pictures Police arrest a suspect in connection with the shooting at the Marjory Stoneman Douglas High School in Parkland, Florida Reuters Florida shooting – in pictures Parents wait for news after reports of a shooting at Marjory Stoneman Douglas High School in Parkland, Florida AP Florida shooting – in pictures Anxious family members wait for news of students AP Photo/Wilfredo Lee Florida shooting – in pictures Students being evacuated from the school AP Florida shooting – in pictures Students being evacuated from the school Getty Florida shooting – in pictures People gather waiting for word from students AP Florida shooting – in pictures Parents waiting for news on their children AP Florida shooting – in pictures People gather at a hotel where students were taken after the shooting Getty Florida shooting – in pictures Florida Governor Rick Scott speaks to the media as he visits Marjory Stoneman Douglas High School following the shooting AFP/Getty Florida shooting – in pictures Dr. Igor Nichiporenko, Medical Director Trauma, left, and Dr. Evan Boyer, Medical Director, Emergency Services, speak about treating victims and the suspect at a press conference outside Broward Health North hospital AP

Meanwhile, Democrats and gun control advocates say that it is simply too easy for individuals to get their hands on deadly weapons. The United States has some of the highest rates of gun violence in the developed world, and it is exceedingly easy to buy a gun. It’s time for a change, they say.

Inside the sprawling expo centre that housed the gun show, rows of long yellow tables provided enthusiasts with a smorgasbord of weapons options, and choices to carry and keep those weapons safe.

Lines of semi-automatic rifles were looked over by potential buyers. Ammunition gleamed on the tables close to offers of $5 instant background checks. Vendors offered up Tasers, knives, and bulletproof vests.

“This will work for all tactical operations,” one vendor told a woman looking at gun holsters, reassuring her that the option she was looking at would serve her needs.

“Listen, you’re always going to have evil. There is evil in this world,” a different vendor told The Independent. “We can’t continue to blame the product.”

Jorge Fernandez, the manager of the Florida Gun Show, said that his organisation had chosen to go ahead and open up on Saturday and Sunday because it was planned years in advance. Stopping the event on such short notice would cost tens of thousands of dollars, he said, and impact his business.

“We’re very, very sensitive to what happened in Parkland, we want everyone to know that we don’t want them to think that we’re being insensitive by having the show go forward,” Mr Fernandez said.

A smorgasbord of weapons were on display at the Miami show

“These shows are put in place years in advance. We pay these venues years in advance. We pay personnel. We hire off duty police. We hire security. So having this mechanism in place – this is a business,” Mr Fernandez continued. “To put it in reverse and stop it would cost tens of thousands of dollars, and it would really impact the forward motion of the business.”

For the protesters at the rally, money is partly the point.

Demonstrators lined the sidewalk with signs blaming the gun industry and its allies – and its vice grip on a certain faction of Congress – for creating circumstance where a 19-year-old man who many have now said seemed off-kilter could legally, and easily, buy a semi-automatic weapon that he would later use to massacre a school.

“The NRA are buying politicians,” Joanna Peterson, 36, a Fort Lauderdale high school English teacher said, holding her seven-year-old daughter’s hand.

Ms Peterson noted that the gun industry donates millions to primarily Republican politicians, including Florida’s own Sen Marco Rubio.

Assault rifles on sale at the Miami fair

Mary Ann Benitez, 49, had come with her 13-year-old daughter, Amanda, and said that the shooting in Parkland brought the issue frighteningly close to home. Her son is a freshman at the school she said, but wasn’t in the building where the shooting occurred by chance.

“I think we can make it harder, and save lives in the future,” Ms Benitez said, noting that she does not expect every mass killing to be stopped by new gun restrictions.

Ms Benitez said that Parkland, where she lives, is generally a safe community. People forget to lock their front doors, and their cars. It’s a gated community that has been terrorised by unimagined evils.

The demonstrators said they realise that the shooting in Southern Florida is just the latest time America has seen mass murder, and that little has been done in light of those events. But, for those who showed up, that does not mean hope is nonexistent.

Two young women hug at a police checkpoint near the Marjory Stoneman Douglas High School where 17 people were killed by a gunman on 15 February 2018 in Parkland, Florida. (Getty)

For those in the community, the shooting was a call to arms – a call to begin using their voices to try and ensure another community is not torn apart by a similar event.

“Voices need to be heard. That’s the bottom line,” Stephanie Ferris, 32, said.

Ms Ferris, who has a 13-month-old child, said that political pressure is how she sees change coming, and says she realised that she has to play a part in adding that pressure. Her cousin, she said, was one of the high schoolers at Stoneman running from bullets just days ago.