It was revealed last week that the UK branch of the Overseas Friends of BJP, India’s governing party, is campaigning for the Conservatives in 48 marginal seats at this election. The group cited, among other reasons, the Labour party’s passing of a motion at conference seen as critical of the Indian government’s actions in Kashmir, although the party shifted its stance this week in response to a backlash among Indian voters. British Hindus are also being targeted by WhatsApp messages urging them not to vote for the “anti-India” Labour party.

Such “foreign interventions” fall into a predictable pattern: coverage often implies, inadvertently or not, that Indian voters are more swayed by their ethnic or religious identity than by other factors. This may fit with the “vote-bank” assessments of South Asian democratic politics – the practice of appealing to identities such as caste and religion to consolidate an electorate – but it doesn’t chime with the evidence on how British Asians vote.

So was this a strategy to distract voters, or is there something more interesting – or worrying – happening electorally and politically? It’s certainly true that British Indian voters have recently been moving towards the Conservative party. But this is better explained by existing trends than by a newfound focus on Hindu nationalism as the key political dividing line.

Until very recently Indian voters showed roughly similar support for the Labour party as other ethnic minority groups. For instance in 2010, when 68% of BME voters chose Labour, Indian voters were at 61%, hardly different from the 60% of Pakistani voters who supported Labour too. Economic considerations, including unemployment, were the main factor behind all ethnic minorities’ choice of party.

In the years up to the last general election, ethnic minority support for Labour rose to 77%. But there was a notable difference between groups: among Indian voters the proportion supporting the Conservative party rose to about 40%, and fell to about 55% for Labour. Over the same period, 2010-17, Bangladeshi and Pakistani voters shifted strongly in favour of Labour, with only 5% choosing the Conservative party.

Facebook Twitter Pinterest East Ham in London is one of the most ethnically diverse constituencies in Britain, but as elsewhere no one minority dominates. Photograph: Graham Turner/The Guardian

Already in 2010 there was evidence that, compared with other middle-class minorities, middle-class Hindus were more likely to vote Conservative. So does the strategy of mobilising British Indians against Labour make sense? The Friends of BJP claim they are targeting 48 marginals, even naming those where there is a sitting Labour MP of Indian background. But closer examination indicates that this does not look like a viable electoral strategy.

Lisa Nandy in Wigan, for instance, has been explicitly mentioned as a target, despite having a 16,000 majority in the last election. While it’s true that such large leave-voting constituencies are being targeted by the Conservatives, there are only 413 people who identified as Indian in the last census in Wigan, and it’s hard to imagine that white British leave voters will make a voting decision on the basis of how the major parties stand on Kashmir.

The focus on Tan Dhesi in Slough looks similarly irrational. It’s true that Slough has the 11th most Indian voters in Britain, but that equates to just 15.6% of the local electorate. Furthermore, only 6.2% of the constituency is Hindu, with the anti-Labour appeals implicitly suggesting anyone who isn’t a Hindu nationalist is “anti-Indian”. Yet in Slough there are more Sikhs than Hindus, and more Muslims than either, so it seems particularly inadvisable to appeal to Hindus with an anti-Muslim, anti-Sikh message.

This suggests two wider points: first is that among the 1.5 million Indian people in Britain only 44% ticked a Hindu box in the last census, with 22% choosing Sikh, 14% Muslim, 10% Christian, and 8% identifying as none or refusing to answer. Whatever the BJP’s vision for India, Hindu nationalism doesn’t have the numbers in Britain to be a winning strategy among British Indians.

Take the 2016 London mayoral election, when Zac Goldsmith ran a campaign explicitly targeting Indians and suggesting Sadiq Khan was tied to Islamists. Goldsmith got the worst overall vote share of any second-placed candidate, and Khan won eight of the 11 wards with the most Indian voters, including the ward with the most Hindu voters.

Second, and more generally, there are no constituencies in the UK where any single minority ethnic or ethno-religious group is a majority. In fact, there are only four where any individual ethnic minority group is more than one in three of the population, and again only four where any single ethnic minority group is larger than the white population.

Consequently, even if ethnic minorities cast their vote based primarily on their identity, it’s not really possible to appeal directly only to one ethnic or religious group to win an election locally. Britain’s constituencies are generally too mixed, comprised of a mix of ethnic groups, most of whom vote for similar reasons.

The BJP’s clumsy and misinformed intervention into British politics does, however, raise some concerns. It may point to a trend of political parties and other less organised groups seeking to mobilise individual ethnic communities on the basis of narrow appeals to that group, without offering a wider political vision. This is a danger not just from Hindu nationalists but from any communalist or sectarian group. For now, geography – the relative diversity and spread of Britain’s ethnic minorities – provides insulation against such appeals.

The second lesson is the global ambition and links of ethnic or ethno-religious nationalism. We’ve already seen British far-right personalities endorse the BJP’s politics. Its vision fits into a global trend of exclusionary nationalism that rejects multi-ethnic democracies and minority rights. Such a politics and policies may be advantageous to Hindu nationalists in India but in the UK and Europe, it would result in all ethnic minorities being discriminated against by a dangerous form of white nationalism.

Anecdotally, there are signs that British ethnic minorities, including British Indians, are worried about and reject ethno-nationalism in the UK. Whatever the motivations of the BJP, British political parties need to reject appeals to ethnic minority groups that are narrow or exclusionary, just as they should reject such appeals to the white British majority.

Building a common vision will require tackling racial discrimination and building solidarity among all ethnic minority groups, something that Britain’s political class need to take more seriously if they are to avoid the divisive and dangerous politics represented by the BJP.

• Omar Khan is director of the race equality thinktank the Runnymede Trust