Nourdin el Ouali has grown used to far-right attacks on Dutch Muslims, and to dog-whistle politics. But when the country’s prime minister wrote an open letter last week, in effect demanding that minorities integrate or “go away”, he was still shocked.

Mark Rutte’s letter comes less than two months before a national election, and after months of watching populist Geert Wilders rising into the top position in national polls. If the election were held tomorrow his far-right party would probably be the largest in parliament.

The letter did not directly mention Muslims, and began instead by attacking people who drop litter or spit on buses. However, in his warning of “something wrong” in Dutch society, the message was clear.

Netherlands PM says those who don't respect customs should leave Read more

Rutte’s naked bid to woo far-right voters for the 15 March election prompted scathing criticism across mainstream society, and worry among Dutch Muslims, who have already endured a sharp rise in hate crime and say they face regular discrimination in daily life.

“It concerns me a lot, because it’s the prime minister who wrote the letter,” says Ouali, a Rotterdam native, founder and city councillor for the progressive Nida party. “You would expect a different role from someone in this position, to rise above it all, bring people together – not writing this kind of letter where he really in a sneaky way talks about Dutch identity, implying there are groups [of Dutch citizens] that are a threat to the Dutch way of life.”

The failure of mainstream leftwing parties to respond to that discourse is one reason Ouali waded into local politics himself three years ago. “They didn’t have a good answer on this rightwing discourse and most of all were patronising,” he said. His party, progressive and inspired by Islam, is the embodiment of opposition to his values.

“We say we have have Rotterdam DNA and Islamic inspiration, we are very diverse when it comes to ethnicity and attitudes to religion. The confessional inspiration is for values like equality, justice, just like the Christian democrat party,” he said.

It has claimed eight seats on local government bodies since it was set up in 2014, appealing to people who felt alienated by conventional politics.

The shift rightwards in Dutch politics has been happening for over a decade, since firebrand Pim Fortuyn burst on to the scene in the early 2000s, with a new form of populism that would be adopted by other far-right groups across Europe.

Gay himself, he eschewed the conservatism of previous far-right groups and instead wooed voters by presenting himself as champion of the Netherlands’ liberal, progressive tradition – in every area except religion, painting Islam as a looming threat to Dutch security and the Dutch way of life.

Facebook Twitter Pinterest Firebrand politician Pim Fortuyn espoused a new form of populism before his murder in 2002. Photograph: Robert Vos/EPA

Fortuyn was murdered in 2002 but Wilders has since taken up his mantle, trying to push the definition of mainstream slowly to the right, with rhetoric so extreme that late year last he was convicted of inciting discrimination.

The court ruling only boosted his poll numbers, though, and Rutte’s letter appeared to confirm Wilders’ political triumph, after a year that has seen the far right emboldened by Brexit and Donald Trump’s victory in the US presidential elections. That win, and Trump’s controversial first days in office, have also helped Wilders by keeping the issues that he claims are key at the top of the news agenda.

“What the Trump victory does, is bring his issues on the agenda and create the impression that refugees and terrorism are our key concerns, rather than the welfare state and economic progress,” says Cas Mudde, a Dutch political scientist currently at the University of Georgia and a specialist in populism and extremism.

The system of proportional representation that first allowed Wilders to flourish makes it unlikely that he will become prime minister. He would need to rule in coalition, and Rutte’s party, the closest ideologically, has already categorically ruled out a deal. Wilders says he feels the same; a previous venture into government together collapsed in bitter acrimony in 2012.

But the apparent adoption of his values by a party that may have courted Wilders’ voters but previously rejected his positions, is worrying for the Netherlands, and dangerous for its minorities, Mudde says.

“The last year or so, since the ‘refugee crisis’, Rutte has taken a stronger position, in which he implies, but never literally says, that there are real Dutch (who seem to be white and non-Muslim) and temporary or conditional Dutch (who are non-white and Muslim),” Mudde said.

“The latter have to adapt to the former, even though many of them are born and raised in the Netherlands, and the latter are the main problem, not the former – even though we have seen an explosion of physical threats and verbal violence from the ‘natives’ towards refugees and anyone defending their right to be in the Netherlands.

“I think we managed to be accepted, because we are born and raised in Rotterdam and we have politicians who were not born and raised in the city telling us what to do.”

The Netherlands too often overlooks the extraordinary stories of refugees, he says, pointing to the dramatic transformation in his own family. “My father came here in the early 1960s, and he cannot write or read. If you see what happened in one generation, you can really talk about a revolution.”

He refuses to accept that Wilders is setting the course for the future. “I am concerned, but I always say that pessimism is for those who can afford it, and optimism is for those who don’t have any other option. I see myself in the second group.”