"WHY do men rape?" asked Leslee Udwin in a recent interview about India's Daughter, her documentary which tells the story of the brutal gang rape on a bus in Delhi that shocked the world in 2012.

"I discovered that the disease is a lack of respect for gender. It's not just about a few rotten apples, it's the barrel itself that is rotten." The rotten barrel she was referring to is patriarchal culture. And that culture is not something that has a nationality or an ethnic identity; rather it pervades all societies globally, though perhaps to different degrees.

Today is International Women's Day and India's Daughter had been originally slated to be broadcast tonight. International Women's Day, first established more than 100 years ago, has long been a day when we focus our attentions on women's rights and welfare, while steadily hacking away at all that is rotten in the structures of the patriarchal barrel. India's Daughter gives us pause for thought on how far we have come and how far we have still to go.

The film was shown in the UK but is banned by the Indian government (though many in that country shared it online). Many of those who watched it were shocked. They were appalled by the story of Jyoti Singh, a young woman who on an evening out with a male friend, took a bus home and was raped, beaten and eviscerated. But they were shocked also by the words of the convicted rapist, who had been driving the bus. The interview with him was endlessly horrifying. At one point, he described how one of the rapists, a 17-year-old, "put his hand in her and pulled out something. It was her intestines ...We dragged her to the front of the bus and threw her out".

Those who perhaps thought that feminism was irrelevant might want to think again. This film is a reminder of how much work there is to do both here and globally. We live in a world where according to World Health Organisation (WHO) research, violence against women is "epidemic" (though I would suggest it is more endemic). Their report, published in 2013, found that 35 per cent of women worldwide have experienced physical or sexual violence. Recent years have brought a steady torrent of horror stories, from the brutal treatment of women by Isis and the kidnappings of Boko Haram to homegrown tales of sexual abuse.

The rape of Singh, now widely referred to as Nirbhaya ("fearless") in India, sparked a global and local reaction, not just because its obscenity was beyond belief, but because, horrible as it was, we know it is not a lone case, in India or in any country. Only a month ago the body of 20-year-old student Ozegcan Aslan, a young woman murdered after she fought back against a man trying to rape her, sparked mass protests in Turkey. It prompted women to share their stories of sexual harassment, violence and fear in an explosive Twitter campaign. Aslan was described by many as Turkey's Nirbhaya.

India's Daughter makes chilling viewing but, obscene rape was, it wasn't the detail of the violence that shocked us most in the UK. Actually, I think what took people's breath away were the quotes from the defence lawyers. "We have the best culture," said lawyer ML Sharma. "In our culture, there is no place for a woman."

"If my daughter or sister engaged in pre-marital activities and disgraced herself and allowed herself to lose face and character by doing such things," said defence lawyer AP Singh, "I would most certainly take this sort of sister or daughter to my farmhouse, and in front of my entire family, I would put petrol on her and set her alight."

That educated men could unashamedly make such comments was what outraged many in the UK. It made us feel as if, for all our failings here, we had come to a different place with regard to gender relations.

But have we? Is our middle-class, educated sense of outrage any different here in the UK from that felt by middle-class people in India? And aren't we guilty of focusing on far-off horrors as a distraction from our own? No country, after all, is immune from this. There have been horrifying rape cases the world over in recent years. In 2012, there was a horrific rape in Steubenville, USA by high school footballers. In the same year, two girls in Fontenay-sous-Bois on the outskirts of Paris reported experiencing daily gang rapes in the high-rise tower blocks, sometimes by scores of boys. Some 1400 children are estimated to have been exploited in Rotherham in the UK.

No country is unsullied by rape and violence against women. Nor is any country free of sexist, demeaning attitudes. Let's also bear in mind this has been a week of outrage over the obscenities that have been shouted on English football pitches, chants and comments that have included "Get your tits out for the lads," and "Show us where you piss from, you slag." As the British Indian writer Bidisha puts it: "Male abuse and exploitation of women (and wider societies' disbelief and stigmatisation of victims and excusal or minimisation of perpetrators) crosses all countries and all societies."

During India's Daughter we learn that the rape of a woman is reported every 22 minutes in India. We know that in the USA, a rape is recorded every 6.2 minutes. In England and Wales a rape was reported every 40 minutes in 2013. In Scotland, in 2013, the figure would have worked at something like one every five hours. Populations are different, reporting levels are different and it is extraordinarily hard to compare levels of violence against women globally. Nevertheless the WHO report suggested that violence against women was significantly lower in the "high-income" zone of Europe, Australia and the United States than many other parts of the world.

How well we are doing relative to each other, however does not matter. What matters is that we unite in combating the attitudes and culture that create violence.

"Let's not forget," says India's Daughter filmmaker Leslee Udwin, "that this is not an Indian problem. There are statistics of offences against women in many other countries of the world, including the UK where we have one out of three young girls between 13 and 17 having experienced sexual violence."

Nevertheless, many people in India feel their country has been misrepresented. I spoke to some Indian activists and feminists who had concerns about the documentary. Most of them felt that the rapist's interview should not have been aired, as it might glorify the rapist's "mindset".

"Violence against women in India is definitely an issue that needs an international spotlight," said feminist campaigner Nimisha Srivastava, "but I'm afraid that this film may create an 'otherising' effect, that such crazy beliefs are widespread in India and thus make most men potential rapists. There are many subtle nuances of urban-rural divide, caste equations along with patriarchal views that are behind such brutalising of women, but these might be ignored."

Kavita Krishnan, a young Indian activist who is featured in the documentary, recently wrote an article airing her misgivings about the film." It does not help," she wrote, "for people in other countries to imagine that such brutality is India's 'cultural' problem; that India's 'backwardness' is the problem; or that gender violence is 'worse out there in India' ... For each of us, whether we are in India or any other country, the most important, useful - and tough - thing to do is to recognise the 'brutal attitudes' that have achieved normalcy in our own culture. To feel shocked by those attitudes when they are far away, located in the exotic other, is easy; to recognise and confront them in our own comfort zone, is much harder."

We should bear that in mind when we tweet our shock or express horror at what happened in India. The British Indian journalist Bidisha was in India in the aftermath of the Delhi rape, and recalls a potent sense of solidarity and anger amongst women and activists there. "But," she recalls, "I was horrified by the international reporting on the crime, which was full of racist generalisations and the colonial arrogance and bigotry which England has never quite shaken off: India represented as barbaric, backward, repressed; Western feminists writing with bleeding hearts and crocodile tears about how best to save Indian women from Indian men, yet totally ignorant of the Indian women's movement itself and unwilling to learn about it."

However, there are also those in India who believe the film can be a profound force for change. Influential columnist Shobhaa De declared: "India's Daughter must be made compulsory viewing in our schools, colleges and government offices."

Of course, this film is only one story, about one rape. It's the story of an aspirational young woman who planned to be a doctor, attacked by men from deprived backgrounds, with brutalising upbringings. It is only one story of violence against women, and there are many more, with different wealth and class dynamics. We should also remember that most of the global violence against women is happens within relationships: worldwide, almost one third (30%) of all women who have been in a relationship have experienced physical and/or sexual violence by their husband or partner.

Why is this kind of violence so prevalent? Udwin's film appears to put forward a theory - and in many ways it's the prevailing feminist theory of our time. She is trying to show a link between a patriarchal culture, and its values, and violence against women. Do we know for sure that this link exists? The truth is there has been little solid research into the links between patriarchal values and violence against women. But I'm inclined to believe she is right.

Male violence against women remains a problem. But we are beginning at least to have a proper conversation about it. As Bidisha puts it: "It's coming out into the open, raw and bloody ... It's only in the past few decades that we have really begun to take a global view of this issue, researching male violence (including sexual violence) in wartime and peacetime, in different countries, listening to survivors, making the effort to study and record. What I can say is that at least we are now - with grief and pain - facing the reality of the scale of male abuse of women and the many forms it takes, from labour exploitation to gang rape, from sexual harassment to denial of education, and how all of these things reinforce each other."

India's Daughter is part of this important conversation. It may be flawed, but it has prompted men and women across the world, including in India, to talk and tweet and cry and express despair. Hopefully that debate will continue after Leslee Udwin launches the India's Daughter global campaign against violence today. But the film is also just one small part of the change. In many ways it was the people of India who really started the India's Daughter movement, not Udwin. It was they who gathered on the streets and protested; and it is those people who offer real hope.

Ami Kumar, who works for the Centre for Social Research, an NGO that runs rape crisis centres in Delhi, believes change is already happening in India, though perhaps not as fast as many would like. "The shift was happening before December 16, 2012 [the day of Jyoti Singh was attacked]. It was like a wave that was growing, growing, growing and it broke. And Congress government lost its election on that. The country's reaction was a very revolutionary one. It was one of the few movements within our recent history which elected out a leader. Teenagers who were expected to be non-political and non-caring, came out on the streets and said: 'No'."

If there were ever proof that we still need International Women's Day, and other days and campaigns like it, it's this. Whether in Turkey, in the name of Aslan, or in America in the name of the Steubenville victim, or here in the name of the victims of abuse in Rotherham, we should take the energy triggered by India's Daughter and use it for change.