Over the past few weeks, thousands of people in the Netherlands have been doing something which would be unthinkable in most other countries. They’ve been dressing in blackface.

As anyone who lives in the Netherlands will know, this isn’t a one-off event, but something which happens every year. According to Dutch myth, Sinterklaas (Santa Claus) spends much of each November and December travelling around the Netherlands, accompanied by his dark-skinned helpers, Zwarte Piet (Black Pete). In towns and cities nationwide, adults and children turn out to welcome them, dressed for the occasion in Zwarte Piet costumes of their own: brown or black face paint, curly ‘Afro’ wigs, thick lipstick and chunky gold earrings. ‘Comedy’ African accents are not unheard of. To many outsiders, it all makes for a shocking spectacle; jarringly at odds with the Netherlands’ reputation as one of the world’s most tolerant and progressive countries. To most Dutch people, however, the tradition remains entirely unremarkable – as integral a part of the festive season as turkey and stuffing are elsewhere.

Recent years have seen some signs of change. Many Dutch schools, for example, now encourage children to paint their faces in bright rainbow colours rather than the usual black or brown. In Amsterdam, authorities decreed that this year’s costumes must include only token dark smudges on their faces, reflecting the modern story that Zwarte Piet is only black because he climbs down dirty chimneys to deliver presents. Yet despite these changes, blackface remains a common sight in most Dutch towns. One recent survey by the broadcaster NOS found that of 223 committees organising festivities across the country this year, only two locations, Amsterdam and Heemstede, planned to stop using blackface characters altogether. According to another study, conducted in secret by the social affairs ministry and leaked to the press, only 21% of Dutch people support ending or changing the tradition. Rumours of Zwarte Piet’s demise seem greatly exaggerated.

Any non-Dutch person living in the Netherlands soon learns to tread very carefully when discussing Zwarte Piet – a foreigner coming out against the tradition risks being treated in much the same way as a Hillary Clinton supporter at a Trump rally. But it’s hopefully still acceptable to ask: why is blackface still so popular in Netherlands, years after it died out elsewhere?

In part, it’s simply a case of good old-fashioned nostalgia. For many Dutch people, dressing up in brown face paint and a curly wig is a cherished childhood tradition; an innocent game which only the worst kind of Scrooge would want to stop. Like Bonfire Night for the British, Zwarte Piet for the Dutch is something which may seem odd to outsiders, but makes their children happy.

Secondly, one can also detect an element of line-in-the-sand-ism. In an age when many other aspects of culture – film, music, fashion, literature – have been internationalised, there’s a perhaps understandable desire among some Dutch people to say: Enough! Zwarte Piet is an authentic part of our culture heritage, and will not be sacrificed on the altar of globalisation and political correctness.

Thirdly, the debate about blackface also reflects the different boundaries which exist in the Netherlands between the public and private spheres. The Dutch are famous for taking a tolerant approach to many aspects of life; from drug use to euthanasia, prostitution to same-sex marriage. This live-and-let-live attitude is part of what makes the country so appealing, but it can also throw up strange contradictions when one person’s exercise of freedom inconveniences another. In a country where individual rights are sovereign, it’s fine to shout in a residential street at midnight, fine to talk noisily in a ‘silent’ train carriage, and – yes – fine to dress up in a costume which others find offensive. For the Dutch, being tolerant includes respecting the right to do things which others think are intolerant.

More broadly, the controversy also reflects wider attitudes towards race relations which can be – to put it delicately – rather old-fashioned. As I wrote in my book about the Netherlands, the role which the Dutch once played in the global slave trade is still barely discussed in schools and museums, and visitors are often surprised to overhear racial epithets and generalisations which would be unacceptable elsewhere. Last year, the leading Dutch newspaper NRC published a review of a book on race relations, written by an Afro-American journalist, under the headline: “N****r are you crazy?” In some countries, a similar headline would spark public protests, political uproar and perhaps even a criminal investigation. In the straight-talking Netherlands, however, it went largely unremarked.

Finally, the debate about Zwarte Piet also reflects the widening fault lines in Dutch politics. The Netherlands is set to vote for a new government in March. With the far-right politician Geert Wilders enjoying strong support for his Trump-like ‘Make the Netherlands Great Again’ campaign, mainstream politicians have little incentive to face down the traditionalists. Mark Rutte, the centre-right Prime Minister who hopes to avoid a defeat by Wilders, has gone on the record as saying that at this time of year his friends of Caribbean descent “are very happy… because they don’t have to paint their faces”. “When I play Zwarte Piet”, the Prime Minister said, “I am for days trying to get the stuff off my face.” Just this week, when the Justice Minister dared to venture that the celebrations might indeed “upset people and encourage racism’, Rutte quickly responded with a statement saying “I myself love Zwarte Piet; I think it’s a fine tradition.”

The Prime Minister is smart enough to understand the political game he’s playing, and has continuously hedged his Pro-Piet statements with calls for “everyone to decide themselves”. However, many others are even less willing to confront the issue. The Dutch are happy to discuss and debate almost anything – Trump, Brexit, delicate personal problems – but anyone who dares question the wisdom of dressing in blackface is likely to be drowned out by chorus of bitter disagreement. In Rotterdam last month, nearly two hundred anti-blackface protestors were detained by police in an operation which Amnesty International condemned as unlawful. Elsewhere, police were fiercely criticised after an official Twitter account shared photographs of officers themselves posing in blackface. Last week, a Dutch-American journalist was reportedly beaten up by right-wing protestors at a Zwarte Piet demonstration. And when the Dutch national children’s ombudsman said recently that Zwarte Piet might be considered discriminatory, she received numerous death threats. Sadly, in a country which prides itself on political liberty and freedom of expression, reasoned discussion about Zwarte Piet is almost impossible – a situation which does the country little credit. In common with the rest of Europe, the Netherlands is changing fast. But when it comes to blackface, change may be a long time coming.