I've only been to Copenhagen once, a long layover in 2016. I had 6 hours to walk the city, which is really all I did. I did have time to have lunch in a college/hipster-y part of town. While eating at a restaurant, the bartender and I talked #guncontrol.
You see, the year before, Copenhagen had had one of the worst shootings in its modern history. A man killed 2 people and wounded 5 cops. The bartender (who spoke flawless English naturally) explained that pretty much everyone in the country agreed on gun control.
He said that people in Denmark didn't understand the US's obsession with guns (a sentiment I've heard often since then from people in other countries). For the Danes, a shooting happened and they were glad they had strong gun control. They'd have accepted even stricter laws.
No, the laws didn't stop yesterday's shooting in Copenhagen (3 dead, more wounded). But it was 7+ years between 2015 and this shooting. It's the worst they've had since 2015. It's absolutely a tragedy; but one America has every few weeks (sometimes not even making national news).
Gun control is not an impenetrable wall, but it's a wall. It works to lessen a flood. Many on the Right (and dishearteningly on the Left these days too) will point to this Copenhagen shooting as proof that gun control doesn't work. But two shootings in seven years proves it does.
They'll say America's bigger population explains the difference, but the stats show differently: 12 in every 100,000 Americans are killed by guns, compared to 1 in every 100,000 Danes. Looking at the European Union in general, it's not even close.
The point of gun laws - the point of any law - is not to make the world perfect but to broadly improve the outcomes of the citizens of the world. This tragedy in Copenhagen isn't lessened because Denmark has gun control laws. But there are less tragedies like it because of them.