On losing her faith…

"Working my way through university as a Dutch-Somali translator, I met many Muslims in difficult circumstances: in homes for battered women, prisons, special education classes. I never connected the dots – I could not see the connection between their belief in Islam and their poverty, between their religion and the oppression of women and the lack of free, individual choice. It was, ironically, Osama bin Laden who freed me of those blinkers. After 9/11, I found it impossible to ignore his claims that the murderous destruction of innocent (if infidel) lives is consistent with the Qur'an. I looked in the Qur'an, and I found it to be so. To me, this meant I could no longer be a Muslim. In fact, I realised then that I had not been a Muslim for a long time."

On her father

"I learned he was sick in June 2008, only a few weeks before his death. I didn't tell my half-sister Sahra that I planned to visit him in hospital in the UK. It's a hideous thing to write, but I didn't really know if I could trust her with that information. I assume the closest members of my family don't actually want to kill me, but the truth is that I have shamed and hurt them; they have to deal with the outrage that my public statements cause, and undoubtedly some members of my clan do want to kill me for that.

"When I arrived at Heathrow, a large black car from the Dutch embassy was there to greet me; another, smaller but even safer, held men from Scotland Yard. We drove to the hospital. To my relief, my father lay alive before me.

"I felt heavy with the burden of everything I had never said to him and the sheer waste of all the years we'd been apart. The only words I could find were trite messages of love, and I said them over and over again. It was too late for anything else."

On her family

"Reconnecting with my extended family – cousins and my own half-sister – who live in the US, the UK and elsewhere, I found them tragically unsteady on their feet. One has Aids, another has been indicted for attempting to murder her husband, and a third sends all the money he makes back home to Somalia to feed the clan.

They all claim to be loyal to the values of our tribe and of Allah. They are permanent residents and citizens of western countries, but their hearts and minds lie elsewhere. I believe that the dysfunctional Muslim family constitutes a real threat to the very fabric of western life. It is in the family that children are groomed to practise, promote and pass on the norms of their parents' culture. It is therefore of the utmost importance that we understand the dynamics of the Muslim family, for they hold the key to the susceptibility of so many young Muslim men to Islamic radicalism. It is above all through families that conspiracy theories travel from the mosques and madrasas of Saudi Arabia and Egypt to the living rooms of homes in Holland, France and America."

On terrorism

"Many people in Europe and the US dispute the thesis that we are living through a clash of civilisations between Islam and the west. But a radical minority of Muslims firmly believes that Islam is under siege, and is committed to winning the holy war it has declared against the west. A larger group of Muslims, most of them in Europe and America, believes that acts of terror committed by fellow Muslims will unleash a western backlash against all Muslims indiscriminately. With this collective feeling of being persecuted, many Muslim families living in the west insulate themselves in ghettoes. Within those ghettoes, the agents of radical Islam cultivate their message of hatred and seek foot soldiers to fight as martyrs. Unhappy, disoriented youths in dysfunctional immigrant families make perfect recruits to such a cause. With continuing immigration from the Muslim world and a significantly higher birthrate in Muslim families, this is a phenomenon we ignore at our peril."

On Muslim integration

"I see three main barriers to the process of Muslim integration. The first is Islam's treatment of women. The will of little girls is stifled by Islam. They are reared to become submissive robots. They are required to comply with their father's choice of a mate, and after the wedding their lives are devoted to the sexual pleasures of their husband and to a life of childbearing.

"The second is the difficulty many immigrants from Muslim countries have in dealing with money. Islamic attitudes toward credit and debt, and the lack of education of Muslim women about financial matters, means that most new immigrants arrive in the west wholly unprepared for the bewildering range of opportunities and obligations presented by a modern consumer society.

"The third obstacle is the socialisation of the Muslim mind. All Muslims are reared to believe that the Qur'an, as "revealed" to Muhammad, is infallible and must be obeyed without question. This makes Muslims vulnerable to indoctrination in a way that followers of other faiths are not. Moreover, the violence that is endemic in so many Muslim societies, from domestic violence to the incessant celebration of holy war, adds to the difficulty of turning people from that world into western citizens. I can sum up the three obstacles to the integration of people like my own family in three words: sex, money and violence."

On racism

"The west tends to respond to the social failures of Muslim immigrants with what can be called the racism of low expectations. This western attitude is based on the idea that people of colour must be exempted from "normal" standards of behaviour. There are many good men and women in the west who try to resettle refugees and strive to eliminate discrimination. They lobby governments to exempt minorities from the standards of behaviour of western societies; they fight to help minorities preserve their cultures, and excuse their religion from critical scrutiny. These people mean well, but their activism is now a part of the very problem they seek to solve. Their efforts to assist Muslims and other minorities are futile because, by creating the illusion that one can hold on to tribal norms and at the same time become a successful citizen, the proponents of multiculturalism lock subsequent generations born in the west into a no man's land of moral values. What comes packaged in a compassionate language of acceptance is really a cruel form of racism. And it is all the more cruel because it is expressed in sugary words of virtue."

On her security

"I have had to pay a price for leaving Islam and for speaking out. I have to pay for round-the-clock security because of the death threats against me. People often ask me what it's like to live with bodyguards. The short answer is that it's better than being dead. It's also better than wearing a headscarf or a veil, which to me represents the mental and physical restrictions that so many Muslim women have to suffer.

"Bodyguards keep me safe. When you live with death threats all the time, you do feel fear, and have horrible nightmares. When a car is parked outside for too long, I ask myself whether I am being watched. If a delivery boy rings the bell, I hesitate. Is he really who he appears to be? Should I answer the door?

"I try to stay vigilant. I don't keep a routine. But I have decided not to stop writing, not to stop drawing attention to the plight of Muslim women and the threat that extremists pose to free thought, free speech and democratic governments. If I were to stop, I don't think it would help my situation. Once an enemy, always an enemy."

• Edited extracts from Nomad: A Personal Journey Through The Clash Of Civilisations, by Ayaan Hirsi Ali, published by Simon & Schuster at £12.99. To order a copy for £9.99 (including UK mainland p&p), go to theguardian.com/bookshop.