The gash that divided them continues to spurt blood today, and for the same reason they broke up all those decades ago - religion.
On January 4, 2011, the proudly unsecular Pakistan saw an assassination. The Governor of the country's largest province, Salman Taseer, was shot dead in a manner almost identical to that of Indira Gandhi in 1984 - twenty-seven bullets pumped into his body at close range by a man employed to guard him.
While Indira Gandhi ordered a military operation at a place of worship, Salman Taseer questioned the validity of a law signed in by a dictatorial regime, a law that had condemned a young mother to death for 'blasphemy'.
But in the eyes of their assassins, the former Indian Prime Minister and the late Pakistani Governor were guilty of the same crime - lack of respect for religion.
Even as religious minorities in Pakistan hold candlelight vigils in support of the man whose progressive ideas cost him his life, just a tad south of the border, a hotchpotch of religious tension is edging its way into newspaper headlines.
In the lull following months of violence, Srinagar is counting down to Republic Day, when an Indian flag might be hoisted at the Lal Chowk, usually the destination of separatist protest marches.
This time, though, it is the end-point of the zigzag route the Bharatiya Janata Yuva Morcha's 'Rashtriya Ekta Yatra' (dubbed the 'Conquer Kashmir March' by Kashmiri separatists) will take.
The BJP's youth wing began their journey in Kolkata on January 12, with the blessings of their parent party and the censure of Jammu and Kashmir's beleaguered Chief Minister Omar Abdullah.
According to the BJP, the move is an assertion of the unity of India, the unity of Jammu and Kashmir. But to many locals, by hoisting of an Indian flag at the Lal Chowk after nineteen years, the Saffron Party is marking its territory.
At the dawn of a new decade, the past of both countries is haunting them by morphing into their present.
In Pakistan, the amendment to a stringent law is being seen as a licence to blaspheme. In India, a party that has always used its Hindutva to propel itself to power is treading a dangerous path, while a party that brands itself as secular is too busy fighting cases against its members and allies to think about anything else.
In 'secular' India, everyone who is not Hindu is deemed part of a minority religion. In Pakistan, it appears that everyone who is part of a minority is seen as a potential blasphemer.
Faith is a personal sentiment. But what happens when the personal sentiments of hundreds of thousands of people are the same? And what happens when these come into conflict with the personal sentiments of hundreds of thousands of others?
What happens when patriotism and religion get intertwined?
The two events that have left the countries tense aren't one-offs. They're microcosmic versions of a stand-off on a much larger scale. What began as a division on religious grounds has blown up into enmity that simply exists, for a reason no one can pinpoint.
Pakistan's secrecy on the progress of the investigations into the Mumbai blasts of November 26, 2008, is matched by India's silence on the progress of the investigations into the Samjhauta Express blast of February 19, 2007.
Both countries are at a juncture where they must define the boundaries of faith within legislation if they hope to leave their ghosts behind.
Perhaps, at least in India, we should begin by defining 'secularism' in the Constitution.
Then, we can decide whether it is possible to run a country by that ideal.
But more importantly, can we ever learn not to provoke, and not to get provoked? Also by Nandini Krishnan: A chargesheet against the CBI Why is India afraid of Dr Binayak Sen? Why can't we Indians laugh at ourselves? Reality shows: Whom are we kidding?
The author is a writer based in Chennai. She blogs at http://disbursedmeditations.blogspot.com
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