Fourteen years ago, on the street where my family and I live in Karachi - on Clifton Road - seven men were murdered. The banyan trees provided sniper cover for the Karachi police. The street lights were shut. The roads were cordoned off.

More than 100 policemen had stood waiting for my father, Mir Murtaza Bhutto, their guns loaded and their orders undeniable. I was 14 years old, my brother Zulfikar six years old, when our father was murdered on the streets outside our home.

My father, an elected member of parliament and a strong critic of the government of his elder sister, Benazir Bhutto - infamous for its corruption, human rights abuses, support for the nascent Taliban in neighbouring Afghanistan and inept leadership - was shot several times. But he was killed with a point blank execution shot to his jaw.

My father and the six other men, all party workers who accompanied him that night as he returned home from a rally in the suburbs of Karachi, were left to bleed on leafy and expansive Clifton Road, a road that faced the British High Commission, the Italian consulate and other high-profile diplomatic enclaves. They died outside the beautifully decorated Clifton Gardens.

My aunt Benazir's government, in power at the time that her younger brother was murdered, stopped our family from filing a police report, a right we had to have returned to us by the Sindh High Courts. Her government arrested all the survivors and witnesses - keeping them in jail for the remainder of her term without access to lawyers, their families, or to us.

The police officers who had carried out the killings were internally cleared in a police review and put back on their beats. All promoted, to this day they remain powerful members of the Pakistani government and of police forces across the country.

Since Benazir's father, Zulfikar Ali Bhutto, Pakistan's first democratically elected head of state, had been overthrown and killed by a military coup in the late 1970s, my aunt had presided over a fractured family dynasty. Her youngest brother, Shahnawaz, was killed in mysterious circumstances in France in 1985. A year later Benazir entered into power-sharing negotiations with the military junta that had killed her father, jailed her and her mother, exiled her brothers and - she believed - had ordered Shahnawaz's killing, in order to take her place in the dirty pantheon of Pakistani politics.

For 14 years my family and I fought for justice in the Pakistani courts, and six years ago I set out to fulfil the last promise I made to my father, hours before he was killed outside our home, that I would tell his story.

I was in the middle of studying for my Masters degree here in London, at the School of Oriental and African Studies, and I was 22 years old. I began the process of writing Songs of Blood and Sword and looking into my family's often tragic and violent histories by cold calling strangers. "Hello, you don't know me, but..."

I travelled across Pakistan to the northern frontiers of the country and across the southern shores of Sindh. I flew to London and Massachusetts and across Europe seeking out lost acquaintances and old lovers.

In 2007 my aunt Benazir was killed in Rawalpindi. In the aftermath, the streets were immediately cleaned up by the authorities, as they were after my father's murder. No police report was filed by the government led by her widower, Asif Zardari, and no criminal cases were launched against her assassins. I hadn't seen or spoken to my aunt for 10 years before her death and the questions I asked of her government's role in my father's murder went unanswered. Meanwhile the Zardari family keeps my grandmother - my father's mother - incommunicado in Dubai. We have not been able to see or speak to her for the past 13 years.

Two months ago, I launched my book in Karachi. That was the last time I was in my home, my city by the sea. To say that I expected outrage, writing as I had about the current Pakistani government's corruption, criminal past and increasingly worrying present, is to put it lightly.

What I didn't expect was the Pakistani establishment's decision to go nuclear. As I sit in London now, on the third leg of my book tour, politics in Pakistan seems ever so personal. Sulking family members, a lugubrious lot who benefited richly from the power and corruption of my aunt's two terms in office and now her husband's, came out of the woodwork.

The men who spoke to me of the violence they suffered under the state have been harassed and threatened. And I, flatteringly, have been turned into a public enemy of sorts. The years of research, pages of footnotes, interviews conducted over continents, and archive material sourced from libraries across Pakistan and Europe are no match for a hysterical state that has a dynastic reputation to protect and has powerful benefactors to answer to, who squirm when faced with the woeful tales of their billions of dollars of Pakistani aid money being squandered.

A fun fact: Pakistan is a nuclear-armed country that recently missed its millennium goals to eradicate polio. Not because we don't have the knowledge, but because we could not secure the constant refrigeration of the vaccines. Pakistan is a nuclear country that cannot provide electricity to its people.

The storm, exciting though it may be, around my book and me is ultimately not important. Persecution is a part of the Pakistani political ethos. What is worrying, however, is the direction of the feckless and autocratic regime of President Zardari, a man who once boasted to the British press that his government was hard at work fighting terrorism from al Qaeda to Aung San Suu Kyi, though no one seemed to have told the president that Miss Suu Kyi is a Burmese democratic campaigner and not an East Asian terror outfit. Details, mere details.

In the past two weeks, the state has banned access to Facebook, YouTube, Wikipedia and another 500 (or is it 1,000?) websites ostensibly because there is anti-Islamic material on those sites. Omar Zahid, a senior Pakistani television producer, has been raising alarm bells - falling on surprisingly deaf Western ears - reminding those who would excuse the Pakistani government's blanket censorship that "exchange of information has become a very powerful force in Pakistan".

Eric Schmidt, Google's CEO, said: "I'm always suspicious of these broad bans. In every case we looked at, there is an official reason, then another reason. There is an awful lot of political criticism they are blocking at the same time. I am very suspicious here."

Meanwhile, business carries on as usual. On May 18 President Zardari pardoned his unelected interior minister, Rehman Malik, who had been convicted of corruption in 2004.

In the Frontier province, a seventh-grade student, Natasha, the daughter of a poor local stone crusher, was held by police officers and raped for 21 days. After bravely filing police reports, Natasha's family has yet to see a single one of her accused rapists discharged from the police force or brought to justice.

No10 Downing Street and the White House have kept shtum on both cases.

What, then, is the difference between the "democratic" regime of Asif Zardari - who, like the dictator Pervez Musharraf, disdained national elections and was chosen by his own parliament - and the burgeoning Pakistani Taliban? Both oppose freedom of expression, both use Islam to rally people around their oppressive causes, both would ignore the rights of women - under this government, a woman may still be stoned to death for adultery. Who needs the Taliban?

This is the state that Britain and the US support, financially and politically, as the only option to keep Pakistan's Islamists at bay. Perhaps it's time for a new argument to justify this indefensible support of Pakistan's regime? Or not.

FATIMA BHUTTO

Born: Kabul, Afghanistan, May 1982.

Age: 28.

Status: Single. Might adopt children.

Education: American school in Karachi; degree in Middle Eastern Studies at Columbia, New York; MA at London's School of Oriental and African Studies.

Lives: Bhutto family home in Karachi with Lebanese stepmother, Ghinwa, adopted six-year-old brother and 19-year-old half brother Zulfikar.

CV: Campaigning journalist.

Family history: No contact with her Afghan mother, Fowzier. Her father, Mir Murtaza Bhutto, shot dead in Karachi, 1996. In 1985, her uncle, Shahnawaz Bhutto, was poisoned in France. Fatima and her cousin, Sassi, found the body. Fatima's grandfather, Zulfikar Ali Bhutto, fourth president of Pakistan, executed in 1979. Estranged aunt and president of Pakistan, Benazir Bhutto, assassinated in 2007.

Fatima Bhutto talks to Aminatta Forna at the Hay Festival on Bank Holiday Monday at 10am.

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