I did warn him. Shortly after he became the first Muslim to attend cabinet, I urged Sadiq Khan to be prepared. The Islamophobes, the new McCarthyites, would at some stage come after him. He laughed it off. Yet it was only a matter of time. In the current climate of anti-Muslim hysteria, it was perhaps naive of Khan and his advisers to believe that he could run for City Hall as a proud and public Muslim without being targeted or smeared.

Consider the recent spate of newspaper headlines: “Exposed: Sadiq Khan’s family links to extremist organisation” (Evening Standard); “Khan joined radical imam at rallies” (Sunday Times); “Khan linked to ‘online bin Laden’” (Daily Telegraph); “Sadiq Khan gave speech with ‘black flag of jihad’ flying” (the Sun).

These stories basically boil down to: hard-working constituency MP and former human rights lawyer who campaigned against the extradition of a constituent, Babar Ahmed, to the US on terrorism charges, and for the release of British resident Shaker Aamer from Guantánamo Bay, may, in the process, have shared platforms with allegedly unsavoury characters who’ve made unpleasant remarks. Quelle surprise.

What of his “family links” to extremists? Apparently, a man who was once married to Khan’s sister may have spoken at events organised by al-Muhajiroun back in the 1990s (though this is disputed). Seriously? Is that it? Are we all now responsible for the political or theological views of all our relatives? In this case, not even a blood relation, but a former member of Khan’s extended family. Where does it end?

Islamophobia plays right into the hands of Isis | Owen Jones Read more

This is not merely guilt by association; this is the rightwing media’s favourite game of “six degrees of Islamist separation”. Khan isn’t the first victim – and won’t be the last. Everyone from former Tory cabinet minister Sayeeda Warsi – who warned that Islamophobia had “passed the dinner table test” back in 2011 – to ex-Respect chair Salma Yaqoob, to Muslim schoolteachers in Birmingham, have been subjected to similar smears, suspicion and innuendo. British Muslims aren’t blind; they see the way the likes of Khan or Warsi are treated and draw the only obvious conclusion – Islamophobia has been mainstreamed in modern Britain.

The journalists who penned these recent pieces on Khan may, rightly, protest that they are not Islamophobes and ask, “Should we not report this stuff?” To which the response should be: “Do you seriously believe Khan is a secret extremist? Or that he once held, or sympathised with, extreme views? If not, why suggest that to your readers? How is that not a smear?”

Khan, as they well know, has been outspoken in his denunciations of extremism and terrorism – including in the pages of the Sun – and even upset many fellow British Muslims last year by accusing them of “burying their heads in the sand” over the extent of the Islamic State threat to the UK.

And consider too the rhetoric from some of Khan’s political opponents. Last September, during Labour’s mayoral nomination race, a volunteer on rival Tessa Jowell’s campaign told a party member: “Long term you have to consider that Sadiq Khan is a liability because he’s a Muslim” (a comment that Jowell, to her credit, immediately disowned and apologised for).

In December, Tory mayoral candidate Zac Goldsmith’s campaign had to investigate a canvasser who, while distributing leaflets in south London, allegedly referred to Khan as “the Muslim”.

Goldsmith, like Jowell, isn’t an Islamophobe. He has been a friend of the Kingston mosque in his west London constituency, and called for a “zero-tolerance approach toward hate crimes”. Yet he still had no qualms about referring to Khan as “radical” and “divisive” in a campaign leaflet. Do I have to remind him that, in an era in which radicalisation is associated almost wholly with violent Muslims, this is a deeply irresponsible use of language? Can the normally sensible, Eton-educated Goldsmith be unaware of this? (On a side note, the Tory mayoral candidate’s own former brother-in-law, Pakistani politician Imran Khan, has been accused – unfairly, in my view – of being a “Taliban apologist”. Should this be “news” too? Of course not, but the media double standard here is pretty brazen.)

At a Tory campaign rally in January, the prime minister said the capital needed a mayor who would be “tough on Islamist extremists that want to divide our country” – the implication being that Khan wouldn’t be. An aide to the Labour mayoral candidate later described David Cameron’s comments as a “dog whistle” to London’s voters – one in three of whom told YouGov in August that they would be “uncomfortable” having a Muslim mayor.

The irony is that Khan’s election to the mayoralty would be a massive victory in the battle against extremism and terrorism. His arrival in City Hall would be a stark rebuttal of Isis-inspired claims that the west is at war with Islam, that democracy and Islam cannot be reconciled, that Muslims have no future in Europe. It is difficult to overstate the huge symbolism and historic significance of a Khan win on 5 May.

To have a Muslim elected mayor of London, with a bigger personal democratic mandate than any other politician in Europe bar the presidents of France and Portugal, would strike a significant blow against the simplistic narratives of Islamophobes and Islamists alike. (This isn’t, incidentally, an endorsement of Khan’s candidacy, nor should religious background ever be a reason to vote for, or against, a candidate. It is simply an observation of fact.)

To have a Muslim elected mayor of London would strike a significant blow against the Islamophobes and Islamists alike

Remember: here is a Muslim politician who has regretted his party’s “unacceptably anti-Jewish” image, received death threats for voting for same-sex marriage and campaigned to save his local pub in Tooting. I have said it before but I will say it again: if the likes of Khan are “extremists”, then who are the “moderates”? Which British Muslims will be allowed to succeed in public life, without being maligned or defamed?

As Khan himself told me in 2014, he had spent “the past 20 years of my life going to different diverse communities and [saying] get involved in civil society, get involved in mainstream politics”.

“If the impression is left that somehow you becoming involved” in public life results in accusations of extremism, he explained, then “you say, ‘You know what, I can’t be bothered.’”

Surveys show London’s Muslims want to make a difference, to contribute to their communities and stand for office. The shabby and calumnious treatment of Khan’s candidacy by his opponents will only serve to deter those members of a marginalised and demonised community from coming forward. Then the radicals and extremists will really have won – and we will all be the losers.