IN JUNE Narendra Modi, India’s prime minister, spoke of the role that music plays in “breaking all social barriers” in the country. He said that Indian music, an important part of the nation’s cultural heritage, is rich in its diversity and able to unite people regardless of religion or caste. Mr Modi pointed to the “Hindustani music of the north, Carnatic music of the south, Rabindrasangeet of Bengal, Jyoti Sangeet of Assam and Sufi music of Jammu and Kashmir” in particular, as “all these musical traditions set the base of our Ganga-Jamuni tehzeeb”: a syncretic Hindu-Muslim culture.

It is a nice thought, but a misleading one, as music has been squarely in the line of fire in India’s culture wars. Right-wing Hindu nationalists consider Carnatic music—composed and sung by musicians from upper-caste Brahman families—to be the last pure corner in the nation’s classical music scene. It relies upon a vocalist’s ability to sing and improvise from hundreds of combinations of chromatic scales, known as ragas. It is affiliated with Hinduism, often drawing on religious poetry which dates back to at least the 17th century (legend dictates that the songs are a direct gift to humanity from the gods). Many Carnatic tunes are bhakti, devotion to a favourite god in the Hindu pantheon, and narrate the god’s story, their kind deeds, adventures and love affairs. Songs about the childhood of Lord Krishna, the most mischievous deity, are particularly popular.

Hindustani music, by contrast, has been shaped by successive Islamic rulers, particularly the Delhi Sultanate in the 13th century and the Mughal empire. It retains elements from Persian and Arabic cultures such as ghazal, a poetic form. That era of the nation’s history has become increasingly unfashionable, with Smriti Irani, a member of Mr Modi’s Bharatiya Janata party (BJP), even calling to “Remove Mughals From Books” in 2016. Many Hindu nationalists view such Islamic influence as alien and corruptive.

Carnatic music with Christian and Muslim themes is therefore considered base, and in recent months musicians who have embraced interfaith music have come under attack. In August O.S. Arun, a Carnatic vocalist, was forced to cancel a concert with T Samuel Joseph, a popular Tamil Christian producer, after he received abuse on social media and complaints from upper-caste Hindus and organisations. Ramanathan Seetharaman, the founder of a fringe group, is alleged to have threatened Mr Arun over the phone. “Christian and Islamic religious musicians do not sing Hindu sacred music,” Mr Seetharaman told the BBC, “so why should our Carnatic musicians sing their songs?" Mr Arun’s American tour was also cancelled.

Days later Nithyasree Mahadevan, a prominent singer, was forced to apologise for devotional songs referring to Christianity and Islam. “I was happy to be an instrument to bolster communal peace and harmony,” she wrote on Facebook, but lamented “inadvertently hurting your feelings”. Other musicians took a more defiant approach. “Considering the vile comments and threats issued by many on social media regarding Carnatic compositions on Jesus,” T.M. Krishna (pictured), a vocalist and activist, Tweeted, “I announce here that I will be releasing one Carnatic song every month on Jesus or Allah”.

The idea of a “pure” Carnatic music is a myth—albeit a seductive one. The single most important instrument in Carnatic accompaniment today is the violin, introduced by Christian missionaries to Vedanayagam Sastriar, an early composer. Carnatic hymns in praise of Jesus and Allah have been sung for over a century: the “Bethlehem Kuravanji”, also known as “The Girl from the Hill Country of Bethlehem”, is a well known 19th-century composition by Vedanayagam Sastriar, a musician and court poet. Chinnaswami Mudaliar, another Christian, was the first to preserve and record Carnatic tunes through notation. Before the publication of his book in 1870, songs were passed down orally from generation to generation.

Indeed, a syncretic approach has helped to win back audiences bored of the traditional fare. Fusion music, combining Hindustani and Carnatic songs with Western hip-hop, rock and pop, is popular with younger Indians. Mahesh Raghvan, as part of a project called “FLAIR: Carnatic Music 2.0”, posts covers of hit songs using bansuri (a bamboo flute), tabla (traditional drums) and his iPad. A cover of Adele’s ballad “Hello” has been streamed 2.2m times on YouTube; a version of “Despacito”, a reggaeton pop song, has been played 5.8m times. “Some purists don’t like anything new being done to the form. But the new generation does not listen to that form as much,” Mr Raghvan said. “My music acts as a starting point for them.”

All this matters little to hardline nationalists. Few artforms have escaped their scrutiny. Cinemas were attacked last year after a film about a 14th-century Hindu queen was thought to include a dream sequence showing intimacy with a Muslim emperor (Sanjay Leela Bhansali, the film’s director, said that such a scene did not exist). Protestors took to the streets of Kerala in July to call for a ban on “Meesha”, a novel which they thought portrayed religious Hindu women in a negative light. Despite Mr Modi’s rhetoric, it is clear that culture is a powerful tool to erect social barriers in India, not just break them down.