Here are some other disturbing statistics before we move on to why gun laws in the US are in limbo.
The US has less than 5 percent of the earth's population but more than 46 percent of civilian-owned guns, according to a 2018 report by Small Arms Survey.
Equally shocking, the US had 120.5 guns per 100 residents in 2017, according to Small Arms Survey, an independent research project that researches small arms.
On the other hand, around half of the US population, roughly 53 percent, are in favour of stricter gun laws.
So where is the country going wrong?
The Second Amendment
The Second Amendment to the US Constitution reads:
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
There have always been diverging opinions about what "a well regulated militia" means. What constitutes a militia? And what constitutes a "people"?
That question was made partly irrelevant when the Supreme Court of the US gave a landmark decision in District of Columbia v Heller (2008), in which it stated that the Second Amendment gave every individual the right to keep and bear arms, even if they are not connected with service in a militia.
"There seems to us no doubt, on the basis of both text and history, that the Second Amendment conferred an individual right to keep and bear arms," wrote Justice Antonin Scalia in his majority opinion.
The Senate Filibuster
Adding to the US' problem is the Senate. For a bill to become a law, 60 votes are needed in the Senate to defeat the filibuster, which is when senators stop the debate and move on to voting.
But in such a polarised Senate, those numbers are impossible to achieve, and that has been the case for years.
For example, in the aftermath of the infamous 2012 Sandy Hook shooting, there were two bills that promoted gun control and tougher background checks. One of them got only 54 votes in favour, while the other one got 40.
And that’s the problem, the Republicans just won’t do what it takes to prevent these mass shootings, which is vote in favour of gun control in the US Congress.
States in the US can make their own laws about gun control.
Many state laws have gotten less tough in recent years, like Vermont, which allows 16-year-olds to carry weapons without a permit or the permission of their parents.
Republican states like Alabama, Alaska, Kansas, Ohio, Texas, and Utah among others, allow the public to carry a handgun, either openly or concealed, without a licence or permit.
A Strong Gun Lobby Led by the NRA
We can't talk about unrestricted access to guns in the US without talking about the NRA, that is, the National Rifle Association.
The NRA is one of the most powerful pro-gun lobbies in the country. It is powerful because it has money, and a lot of it. The NRA spends about $250 million per year, which is more than all gun control advocacy groups in the US combined.
A big chunk of that money goes into the political campaigns of their preferred candidates, who are pretty much always from the Republican Party.
But it’s not just the money. NRA officials have a very powerful ability to mobilise a grassroots support and to make people vote.
The Republicans know this. They know that they need to keep the NRA happy to win elections, and that is why this lobby has a huge say, if not the last say, in what happens with gun laws in the country.