A curfew is like a collective strangulation. You proscribe movement, talk, communication and assembly. You cut off the very sustenance of life: food, milk, medicine. You choke a people, because you fear, no, dread, what the curfewed other might say to the world. Indian-controlled Kashmir has been under curfew for the last five days; everything is shut down, locked up, besieged. Newspapers have been seized, editors verbally instructed by police officials not to print, TV channels, except of course the government-run ones, have been blocked. People are not allowed to travel except if you have a bullet in your body and are still breathing inside an ambulance. This latest imposition – Kashmir's modern history is bookmarked by chapter after chapter of sieges and martial-law like curfews – came soon after Mohammad Afzal Guru was hanged by India for his involvement in the attack on India's parliament in 2001 in which nine people were killed.

In a case widely criticised for its dodgy investigation, the absence of a fair trial and most crucially, the lack of evidence beyond reasonable doubt, the supreme court of India, upholding sentences of lower courts, sentenced Afzal Guru to a double death sentence in 2005. There was only circumstantial evidence against him, the court admitted, but the "collective conscience of society" could only be soothed with this execution. As soon as what many call a miscarriage of justice was performed in Delhi's Tihar Jail, the Indian government effectively shut off the Valley from the world. It was almost automatic, a reflex, and why wouldn't it be, for the powerful and increasingly militaristic Indian state is well rehearsed in dealing with the oppressed and weak of Kashmir.

So the run of play in this heartless display of retributive justice was this: you hang a Kashmiri in Delhi and then, to complete the picture, to make the performance full, immediately put Kashmir under a military siege. A country that needs to impose a curfew every time it fears what it calls "unrest" in a region that it claims as an integral part should by now have learned that it is not an integral part. It never was.

It was not just the hanging but also the manner of it – executed while the world slept, in secret and in great haste, as thieves do when they embark on their dark deeds – that makes this execution a symbol of the deep moral rot at the heart of the Indian state. Indian authorities chose not to inform Afzal Guru's family prior to the hanging and quietly buried him in prison. His brother has said they learned of his execution on TV. A letter sent by the government of India to Afzal Guru's wife reached her two days after the execution. Even the public prosecutor responsible for Afzal Guru's trial has admitted that it was a violation of his rights as well as of India's prison manuals that state a person on death row must be allowed family visits.

What kind of state makes sure that the wife and young son of a man it is about to execute, do not see him, touch him or hear him talk, one last time? Kashmiris, in mourning and in fury, erected a tombstone over an empty grave in the main martyrs' graveyard in the Kashmiri capital, Srinagar. The text of the epitaph was the same as that of another epitaph, erected in memory of Maqbool Bhat, the founder of Kashmir's main pro-independence militant group turned political formation the Jammu and Kashmir Liberation Front, who was hanged in the same jail 29 years ago. The epitaph reads, "The martyr of the nation, Mohammad Afzal Guru, Date of Martyrdom: 9th February 2013 Saturday, whose mortal remains are lying in the custody of the Government of India. The nation is awaiting its return."

On the morning of 13 February, Kashmiri news websites reported that the police had removed and destroyed the tombstone and then, after the news spread via Twitter and Facebook, a replacement tombstone mysteriously reappeared. The Kashmiri phrases, Qabr Chhoor and Kafan Chhoor, titles for those who rob graves or shrouds are deployed to describe the basest of thieves. The swiftness of the execution, and the macabre theatre that followed, which included an offer by the Indian government that Afzal's family will be allowed to pray once by his grave in prison that the family promptly turned down, is disturbingly reminiscent of Franco's Spain.

I learned of the execution in London and struggled to make sense of it. I still do. It was, for reasons moral and legal – judicial review is available to even people denied a presidential pardon – somehow unbelievable, although by no means unexpected. Does the world's so-called largest democracy really want to be seen as a nation revelling in a retrograde, made-for-TV bloodlust?

I began to think of Ghalib, Afzal Guru's 14-year-old son, who, accompanied by his mother a few years ago, went to the head of the Indian state with a mercy petition, begging the president to pardon his father's life. Clearly, the president wasn't listening. He had to, as the judge had decreed in the supreme court of India's verdict, satisfy the "collective conscience of the society," which will "only be satisfied if capital punishment is awarded to the offender".

It is of course impossible to understand the complex moral arithmetic necessary to arrive at the perfect potion needed to assuage the collective conscience of a billion people. I began to think of writing about it, answering an urge to say what I, and many others, felt. I struggled, despairing about the powerlessness, and perhaps pointlessness, of an op-ed or essay. I also began to feel lonely, for in spite of the proliferation of conversations on social media, a solidarity of the oppressed and the besieged is hard to find amid the buzz of the internet or a postmodern metropolis.

What was the Indian state trying to say, one must ask? Surely, it can't simply be explained, as some analysts have done, as merely a hideous expression of the compulsions of electoral realpolitik in which political parties in India become eager to sink to new moral lows to outdo their rivals. It's a message to the Kashmiri people, an occupying power yelling at the powerless natives that you must bow and genuflect, that the hangman's noose can extend beyond the gallows, casting its dark shadow over children's milk and medicines for old couples.

Two moments seem to have entered history. Kashmiris creating a hollow grave as a mausoleum to memory and resistance and India making a craven declaration: that a Kashmiri corpse can be seditious. It must remain in prison.