Narendra Modi’s visit is an opportunity for Britain to raise sensitive issues

The most remarkable thing about Narendra Modi’s three-day visit to the UK is that it is happening at all. For more than a decade, Britain boycotted the politician – who was then the chief minister of the state of Gujarat – over allegations that he had failed to stop, or had even encouraged, a massacre of hundreds of Muslims in 2002.

In October 2012, Britain decided to re-engage with Mr Modi, as it became increasingly clear that he was set to become the leader of the Hindu nationalist Bharatiya Janata Party and probably the country’s next prime minister. Diplomatically, it was the right move: Mr Modi swept to a landslide victory in May 2014.

David Cameron has long courted India as a business and strategic partner – he has visited the country three times – and the UK has sought to host a reciprocal visit since Mr Modi was elected. But Britain must realise that it needs India perhaps more than India needs Britain.

Since coming to power, Mr Modi has been feted in more than 30 national capitals, as he seeks to promote himself and his country as a place to do business. In truth, doing business with India has never been easy. Although Mr Modi announced that restrictions would be eased on foreign direct investment this week, domestic political realities mean he will not be able to offer the trade liberalisation that many Western nations want – at least not quickly.

But if doing business with India is not easy, it is an endeavour that remains vital. The country has a growing middle class with an appetite for everything from university education to designer clothes. And a successful business relationship with India is not solely of economic benefit to the British Prime Minister, who is keen for any possible route to growth. It would also send out a warm message to a large and growing British-Indian electorate – tens of thousands of whom will cheer his arrival in their country at a special ceremony at Wembley Stadium in London today – which Mr Cameron wishes to woo. This community was considered so important to modern Conservative success that Mr Cameron’s former adviser Lynton Crosby gave it a label, “the Hindu vote” – for which, no doubt, a strategy was drawn up in the weeks preceding May’s general election.

Britain can offer India expertise and skills, and it can also remind Mr Modi how the City of London can play a bigger role in the Indian economy, with plans for Indian companies to raise money in UK markets. Mr Modi will also be courting London investors, who may be able to help to fund his country’s much-needed new infrastructure and plans for digital growth. The longer-term potential for the UK is massive.

The dark history of colonialism has also left Britain with an advantage that it needs to make the most of. Among the 1.5 million Britons of Indian heritage are 10 MPs and 24 members of the House of Lords. Tata Motors is the UK’s biggest manufacturing employer and Mr Modi will visit the company’s Jaguar Land Rover factory in Solihull. In the special relationship, that represents power, soft and hard.

There are sensitivities. Protesters against Mr Modi’s visit are critical of the British Government for apparently failing to stand up to India’s leader on moral matters while happily engaging over the financial ones. Britain must, of course, raise the issue of human rights and ask about progress in the investigation into the deaths of the three Britons killed in the violence in Gujarat in 2002. India itself has been riven by debate over whether the country has become less tolerant since Mr Modi’s election. But whatever Britain does, it must do so with candour and sincerity. India does not wish to be lectured or patronised; it wants to be treated with respect.