Anyone following international news in recent months will be struck by the fact that the gun control debate in the United States has stepped up a gear. President Obama has spoken out numerous times on the issue, calling for more gun control reforms to make mass shootings "rare as opposed to normal". Now it has become a "big difference" in the Democratic race between Hilary Clinton and Bernie Sanders.

This is an issue that clearly needs to be addressed. In a country with more than 300 million firearms, there were at least 13,381 firearm deaths in 2015. Its relevance, though, in the lives of most Europeans seems, at first, to be nothing more than macabre fascination. What does America's love affair with the gun have to do with us?

Certainly, there are major differences in cultural and legal approaches. Ireland’s government accepts what the US struggles to – that gun control works. Recent changes in the firearms law testify to this, with Minister for Justice Frances Fitzgerald saying: “I am determined to prevent any proliferation of handgun availability in Ireland.” And while many of the civilians who own an estimated 300,000 guns in Ireland might find the current laws too strict to their liking, few acknowledge the US model is one to be copied. As one Irish firearms dealer said, they wanted nothing to do with US gun culture for whenever the subject was brought up it ended up discrediting law-abiding gun owners in Ireland.

But even if you are not a gun owner, the US gun debate should concern people beyond America's shores. The fact that many gun sales can be conducted there without background checks has profound international consequences. This was most directly felt in Ireland at the height of the Troubles when many of the IRA's guns came from the United States. US-made AR-18s and AR-10s were common – some even smuggled over in coffins.

Of course, the counter-argument to this is that US guns also helped overthrow English despotic rule in Ireland, but the humanitarian harm committed today with US guns outside America's borders should still appall.

It is estimated that a quarter of a million illicit guns flow south of the US border into Mexico every year. The devastation they bring cannot be underestimated. One report found the number of homicides in Central America between 2003 and 2012 increased by 99 per cent: 139,256 homicides in 2012 alone. In San Pedro Sula, Honduras, considered the most dangerous city in the world, the homicide rate is 169 per 100,000. Ireland, by contrast, has a rate of about 1.2.

We know that many of those Central American homicides were, according to the US government’s own data, using US guns. We also know that simple US gun controls affect this level of violence. Research into the lifting of the US Federal Ban on Assault Weapons in 2004 showed a 40 per cent rise in homicides in those parts of Mexico south of the American states where the ban was lifted. There was no rise in murders south of those states where it was not.

The Second Amendment has other political consequences too. It roots the idea of guns as a central way to govern – both at home and abroad. Guns are seen as a quick diplomatic answer; the US throws firepower at a problem. An Associated Press report in 2013, for instance, claimed the department of homeland security planned to buy over 1.6 billion rounds of ammunition over five years. It had already bought 360,000 rounds of hollow point bullets and 1.5 billion rounds in 2012. Such largesse has deep consequences.

The Pentagon, for instance, has admitted about 321,000 weapons given to the Afghan National Army could not be accounted for. It also lost track of over 190,000 rifles and pistols given to Iraqi security forces. Without question, these US-produced guns have found their way into the hands of Isis. Ammunition magazines “identical to those given to Afghan government forces by the US military” have been found on dead Taliban fighters.

So, when Ireland recently announced its intention to take in 4,000 refugees, you have to consider this hard truth – these refugees are fleeing crises wrought by the use of guns and explosive weapons in populated areas. Some of those were US made and the conflicts they are fleeing from were certainly fuelled by US armed intervention.

There is one final way in which the American gun debate has global consequences. Their constitutional right to bear arms has effectively inhibited effective global gun control treaties.

It is well known that the US gun lobby is deeply influential domestically. Eight US presidents have been life-long members of the National Rifle Association. What is lesser known, though, is the impact the US gun lobby has had globally – but it has been so divisive that the charity Amnesty International had to tell the group to stop its campaign of lies at the United Nations. It's an influence best summed up by the fact the current chairman of the NRA's international affairs subcommittee is John Bolton. Bolton was the onetime US ambassador to the UN and the diplomat who effectively hobbled the Programme of Action on Small Arms and Light Weapons – the UN's largest attempt at stemming the illicit gun trade to date. Bolton watered down the most compelling aspects of the treaty. Today, partly because the world's largest small arms producer refused to support its bolder initiatives, the Programme of Action is considered by many as having largely failed.

Of course, it is not just the US’s relationship with guns that concerns. Russian and Chinese guns have caused untold harm, not to mention other major EU arms manufacturers. But Russia and China aren’t viewed as fully functioning democracies, and the EU’s gun producers have limited sway politically.

The US, though, embraces political support from gun makers. It throws guns at a diplomatic problem rather than opting for less violent means. It fails to stem the flow of US guns falling into the wrong hands. This is why the US gun debate is important. It has consequences the world over – even in Ireland – and these are consequences that should be addressed, both at home and abroad.

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25 curious facts about guns

1. There are almost a billion guns in the world.

2. An estimated 12 billion bullets are produced every year.

3. Home to just 14% of the world’s population, Latin America accounts for 42 per cent of all firearm-homicides worldwide.

4. Alaska has a firearm suicide rate 700 per cent higher than New Jersey.

5. The deadliest mass shooting was by Anders Behring Breivik in Norway in 2011, where 69 died in a shooting spree, and a further eight lost their lives in a bomb blast.

6. The first gun assassin to enter the history books appears to have been a Scotsman – James Hamilton. He shot James Stewart, the half-brother of Mary Queen of Scots.

7. The father of Woody Harrelson, the star of Natural Born Killers, was a contract killer, convicted of assassinating US federal judge John H Wood, Jr, the first federal judge killed in the 20th century

8. Santre Sanchez Gayle was Britain’s youngest hitman – just 15 when he shot a young mother for £200 in Hackney in London.

9. Researchers found the average cost of a hit in Britain between 1974 and 2013 was just over £15,000.

10. One survey of American police sharpshooters found that 80 per cent of all recorded ‘hot’ incidents were fatal – about half the suspects were hit in the head.

11. More police officers were shot and killed in the US in 2014 than were shot and killed in the last 50 years in Great Britain.

12. In the American civil war, guns accounted for about 75 per cent of combat casualties. In the second World War only about 18 per cent of military casualties had been shot.

13. About 6 billion bullets were shot by US forces in Iraq between 2002 and 2005.

14. German snipers in the second World War got wristwatches after 50 kills; a hunting rifle after 100; 150 kills won a hunting trip with Heinrich Himmler.

15. The 1900 Olympic games in Paris held a live pigeon-shooting event – the first and only time in Olympic history when animals were killed purposefully.

16. Hitler’s golden 7.65mm Walther PP sold for $114,000 at a 1987 auction to an anonymous bidder.

17. US hunting supports an estimated 680,000 jobs: the $26.4 billion in salaries and wages being larger than the entire economy of Vermont.

18. A lion hunt can cost up to $70,000, and a permit to hunt a black rhino recently raised $350,000 at auction.

19. With the exception of New Zealand, Hong Kong, Japan, Korea, Tonga and Latvia, more men are killed as a result of armed violence than women.

20. Only nine states in the US prevent people jailed for stalking from, once released, purchasing a gun.

21. Levels of gun violence in mainstream American films have more than doubled since 1950, and the levels of gun violence in PG-13 rated films now outpace those of R-rated films.

22. At almost 130,000, there are about 10 times the number of federally licensed firearms dealers in the US than McDonald’s.

23. At the end of the Cold War as much as 2.5 million tons of ammunition and as many as 7 million small arms and light weapons were left behind in at least 184 depots in Ukraine.

24. In 2006 the UN reported that a quarter of the $4 billion annual global gun trade was illegal.

25. At one point over 300,000 Afghan warriors in the 1980s carried weapons provided by the CIA.