The warning signs were there. Hindu nationalists have long desired to end the semi-autonomous status of Kashmir, India’s only Muslim-majority state; the ruling Bharatiya Janata party has long said it would do so. Suspicions rose when thousands more security forces poured in around a week ago, and when pilgrims and tourists were ordered out, supposedly due to fears of a terrorist attack.

Yet the revocation and decision to split the state in two – creating two centrally administered territories in its place – is shocking and perilous. Several legal experts believe it unconstitutional too. Its abrupt and ruthless manner, with the house arrest of well-known politicians, imposition of a curfew and blackout of the internet and phone lines, will likely lead to protests and inflame the resentment which has underpinned an insurgency which has cost tens of thousands of lives. Though it has ebbed since its horrific peak two decades ago, the violence has crept up again more recently: 2018 was the bloodiest year for a decade. In February, Pakistan-based Jaish-e-Mohammed killed more than 40 soldiers in a suicide car bombing – the deadliest attack on Indian forces there for decades. The youth of the population, in many cases too young to remember the full cost of the conflict in the 1990s, gives cause for worry.

The broader reverberations in an unstable region are as worrying. Pakistan has already condemned New Delhi’s move and said it will “go to any extent” to protect Kashmiris. The two nuclear-armed neighbours have long been at odds – and at times at war – over the disputed Himalayan region; Bill Clinton once described the ceasefire line as the most dangerous place in the world. China, which also has a territorial dispute, declared India’s actions unacceptable and void. The US has been critical in defusing previous crises in the past. But it is harder to place faith in the Trump administration – and Washington is unlikely to be overly interested in the plight of Kashmiris unless the regional peace looks threatened.

Seven decades ago, independence and partition posed Kashmir the choice between two nations. When its ruler agreed to accede to India, New Delhi guaranteed it autonomy except in matters such as foreign affairs and defence. In reality, that has been eroded over the years. A violent insurgency, partly fuelled by Pakistan, was brutally repressed with severe human rights violations. The scrapping of article 370 is in large part symbolic – but nonetheless hazardous for that. Lifting restraints on the purchase of land and permanent settlement by outsiders is almost as inflammatory: many fear a consequent demographic shift.

India’s secularists saw Kashmir’s status as the proof of India’s strength as a multifaith nation. But May’s second landslide victory for the BJP has given Prime Minister Narendra Modi, in power since 2014, free rein to realise his Hindu nationalist vision. Some experts think Donald Trump’s offer to mediate in the dispute with Pakistan and progress in Afghanistan peace talks may have also played a part.

Mr Modi and his allies understand how provocative this move is: why else impose this lockdown? They say these changes will support progress and development in Kashmir. It has already earned the applause of the Hindu heartlands.

In recent years, many Kashmiris have rejected separatism and the majority have placed their faith in mainstream politics. Yet Delhi has cut off communications, locked down the region and put politicians under house arrest. The consequences are likely to be grave.