On Friday 7 April, a hijacked lorry ploughed through the crowd on Drottninggatan in Stockholm, one of the most popular shopping streets in the Swedish capital, killing four and leaving many more injured. The images now being broadcasted around the globe remind us of what happened on the Promenade des Anglais in Nice, at the Christmas market, at the Breitscheidplatz in Berlin or, just a couple of weeks ago, on Westminster Bridge in London. What happened in Stockholm seems to be yet another cruel example of the new low-tech terrorism where ordinary vehicles are turned into deadly weapons in the hands of lone but remotely controlled perpetrators.

This is horrifying. But when flown-in correspondents are suggesting that no one can grasp the fact that this could happen here, in Sweden, a country so open and cosmopolitan, then this does little more than illustrate how short memory is.

In reality, Sweden has a long history of terrorism and political violence.

In 1973, the Swedish parliament passed the county's first "Terrorism Act". Two years earlier, Croats connected to the post-war fascist movement Ustaše had attacked the Yugoslav embassy in Stockholm, shot the ambassador and wounded his secretary. In a hijacking incident at the Bulltofta airport the year after, other Ustaše sympathizers demanded that the perpetrators be released from Swedish prison, which led a parliamentary commission to suggest new legislation.

In 1975, the Holger Meins Commando, a group within the German Red Army Faction, seize the West German embassy in Stockholm, demanding the release of a number of RAF members from prison in West Germany, including Andreas Baader and Ulrike Meinhof. Before setting off several explosions, the terrorists executed two German diplomats.

In 1986, Sweden's prime minister Olof Palme was shot dead, walking home from the Grand Cinema on the central Stockholm street Sveavägen – and 2003, Palme's social democratic heir and Swedish foreign minister Anna Lindh was assassinated in a department store just a few blocks away from where Friday's attack took place.

At the beginning of the 1990s, right-wing terrorist John Ausonius on ten different occasions shot eleven people living in Stockholm, all with a migration background. One died, ten suffered major injuries but survived. Known in the media as the "The Laser Man", Ausonius inspired other terrorists, such as Peter Mangs, who shot numerous people of dark complexion in Malmö 2009 and 2010, and Anders Behring Breivik celebrated him after the attacks in Oslo and on Utøya in 2011, killing 77 people.

And then 2010, two bombs exploded on Drottningatan, set off by Iraqi-born Swedish citizen Taimour Abdulwahab, who has been called the first suicide bomber in the Nordic countries. That time, coincidence – and the sheer clumsiness of the perpetrator – saved Stockholm from major tragedy. Abdulwahab only managed to kill himself.

Even the steady stream of Swedish crime fiction, from Henning Mankell's Wallander to Stieg Larsson's Millennium trilogy, has failed to change the image of Sweden as a peaceful, somewhat naïve and thoroughly innocent country. It seems as if Europe and the world need this exceptional paragon, a role the Scandinavians have played ever since the golden decades of the Swedish model around the 1950s and 1960s.

But how many times can you lose your virginity and still remain a virgin? The reactions after the attack on Friday show that official Sweden has learned its lesson and knows very well that it is a country just like any other, far from a protected Bullerby idyll.

It is only three weeks since SÄPO, the Swedish security police, presented a report saying that there was a high probability for an attack such as the one in Stockholm. The police have in fact been training for exactly this scenario. So, no one was really surprised when it happened. Instead all the prepared plans were methodically implemented, which resulted in a lockdown of large areas of downtown Stockholm.

Simultaneously, the hashtag #OpenStockholm spread through the social networks Swedes are so fond of. Ordinary Stockholmers were opening their houses and apartments for those who couldn't get home when trains and subways stood still: a charger for the smartphone, a place at the dinner table, a sofa to crash on...

This openness has made the people of Stockholm proud – rightfully so. It's an attitude that is far from naïve, on the contrary, it is part of an utterly pragmatic worldview. The goal of the terrorists is maximum polarization, to divide societies and force people to take sides in a war that leaves no room for anything other than that war. The terrorists want to eliminate the spaces in-between.

At that moment, just a breath or two after the attack: a defiant willingness to help and a fundamental openness towards the other, the stranger. That is an act of resistance.

However, it would indeed be naïve to believe that such a horrifying act of violence as last week's attack will leave no trace on politics and society. Populists of all colours know how to make use of images of terror and fear.

"Finally," tweeted Alexandra Brunell, secretary of Jimmie Åkesson, after the last attempt on Drottninggatan back in 2010. Åkesson is the leader of the xenophobic Sweden Democrats, who occupy 49 seats in the Swedish parliament, which amounts to 14 percent. A suicide bomber on the streets of Stockholm was, according to his secretary, above all regarded as a political opportunity. That tweet might have been denounced as shameful, but there will no doubt be those who want to capitalize on this attack as well.

So far, most leading politicians have refrained from making any immediate political points on the attack. How long will it stay that way? Just like the perpetrator in Berlin, Anis Amri – a Tunisian who had applied for asylum in Germany – the suspect in the Swedish case, the Uzbek Rakhmat Akilov, faced expulsion. He applied for a residence permit on 10 November 2014. The application was rejected on 15 June 2016, which led Akilov to go underground. The discussion about the inefficient implementation of expulsion orders has just started.

Next autumn Sweden will have parliamentary elections, but already today, the Sweden Democrats exert – just like similar parties in other countries – considerable influence on Swedish politics, as other parties tend to adopt parts of their agenda, hoping this will make some of the voters come back. Not long ago Sweden received more refugees than any other EU country – by far. Today Sweden has some of Europe's most restrictive asylum and immigration laws – introduced by a red-green government.

Will the attack on Drottninggatan in Stockholm change Sweden? Yes, probably. But not as much as many seem to believe. Because the change they have in mind has already taken place.

Will the image of Sweden change? Perhaps. It would be high time.