The old Pakistani maulawi laid two currency bills on the table between us, one for 50 rupees, the other for 100 rupees. "Now tell me," Rahat Gul asked, "which is the more valuable?" I thought it was a trap – which it was, in a way – but he lost patience with me and seized the 100 rupee note. "Now come with me." And he stood up and led me down a narrow corridor into a small bedroom. There was a camp bed, a military radio and, at the far end, a giant British-made safe. He fiddled with the combination and hauled on the iron door. Then he placed the 100 rupee bill inside and locked the vault. "You see?" he said. "This is like a woman. She must be protected and looked after, because she is more precious than us."

Reader, this is no joke. This whole piece of entirely spontaneous theatre occurred several years ago in what was then called the North West Frontier Province. But I actually possess a videotape of the entire proceedings, in which you see me following the divine to his safe and hear him comparing the worth of the currency bill to the worth of a woman. I was supposed to be impressed by the high status which he accorded women. What struck me, of course, was that this high status appeared to accord women an exclusively economic value – she was a bank account – and that this might lie behind the whole misogynistic system which led us to the curse of "honour" crime.

"Two things will happen when you write your reports about 'honour' killing, Mr Robert," an old Egyptian friend tells me in Alexandria. "Firstly, they will say you are using Muslims as whipping boys – even though this has nothing to do with Islam. And then you will be accused of demeaning the Arab nation or Egypt or Jordan or Pakistan or Turkey." Well, we shall see.

I walk into the office of Ahmed Najdawi, an elderly Jordanian lawyer whose walls are decorated with photographs of his hero, Saddam Hussein. There is even a picture of Saddam greeting a very proud Mr Najdawi. A secular man, then, a man of the people, for Saddam remains a hero to many in Amman. But no, Ahmed Najdawi often represents the families who commit "honour" killings, those who have killed their wives or daughters or sisters.

He believes the whole subject has become "super-exposed" for political reasons, because "Muslims are an easy target". This happens all over the world, he insists. "Although mostly it has to do with Eastern cultures." He talks about the Ottoman empire, how its rules formulated "primitive laws that defended primitive customs", how "customs are stronger than laws."

I know what's coming next. Didn't we Westerners used to treat women the same way? "In Europe, they used to burn women for adultery." Yes, it's true. And not long ago, unmarried British women who were pregnant were locked up in lunatic asylums. Anyway, didn't "honour" matter to European men in the Renaissance?

And back in Beirut, I open my old copy of Shakespeare, to that most bloody of plays, to Titus Andronicus. The hero's daughter Lavinia has been raped and mutilated, and Andronicus is contemplating her "honour" killing.

Titus: Was it well done of rash Virginius

To slay his daughter with his own right hand

Because she was enforced, stained and

deflowered?

Saturninus: It was, Andronicus...

Because the girl should not survive her shame

And by her presence still renew his sorrows.

So Lavinia's fate is sealed.

Titus: Die, die, Lavinia, and thy shame with thee,

And with thy shame thy father's sorrows die.

But does the father's sorrow die?

"There is remorse, for sure," Najdawi says. "They commit these crimes, motivated by the cultural aspects. But when time calms them down, they feel regret. Nobody kills a wife or a sister or a daughter without later feeling remorse."

Yet nothing comes closer to Titus Andronicus than the insistent, terrible stories of gang rape by United States personnel in Abu Ghraib. You hear this repeatedly in Amman, and a very accurate source of mine in Washington – a man who deals with military personnel – tells me they are true. This, he says, is why Barack Obama changed his mind about releasing the photographs which George W Bush refused to make public. The pictures we saw – of the humiliation of men – were outrageous enough. But the ones we haven't seen show Americans raping Iraqi women.

Lima Nabil, a journalist who now runs a home for on-the-run girls, sips coffee as the boiling Jordanian sun frowns through the window at us. "In Abu Ghraib," she says, "women were tortured by the Americans much more than the men. One woman said she witnessed five girls being raped. Most of the women in the prison were raped – some of them left prison pregnant. Families killed some of these women – because of the shame."

Lima has written many articles about Jordan's "honour" crimes. At least one was censored. She has – like other journalists – been threatened. "Out here, we have closed communities, where everyone knows everyone else. In tribal law, in the old days, the sheikh would protect you. Now the government is trying to take over."

Mr Najdawi agrees. "We have just had an amendment to the law – it gives equality to men and women over 'honour'-related issues. It says that a woman must be treated the same way if she kills her husband. But either way, if a husband kills his wife, this is regarded as murder with intent and he cannot receive less than 10 years. However many mitigating circumstances, the crime was still intentional." And it's true that Amman courts have now been handing out 14-year sentences to men for "honour" crimes and intend to make the guilty serve their full sentences.

Lima Nabil tells a story that I hear from three other journalists and NGOs in Amman. The details are the same – and the story is true. In the town of Madabad, a wife left her husband for a lover and they went to the tribal leader to prevent family "honour" being invoked. "The tribal leader gave the husband a divorce and ordered the wife to marry her lover," she says, "Then he ordered her lover's sister to marry the abandoned husband. Thus if the lover claimed he'd stolen another man's wife, the husband could say he was sleeping with his sister!" But each time I heard this tale, I asked myself the same question. Tribal "law" may have prevented violence – but what about the sister who was forced to marry the divorced husband?

Among the toughest of the women to whom I spoke was Frazana Bari. A lecturer at the Qaid al-Azzam University in Islamabad, she makes frequent appearances on television, and manages – by her free thinking – to provoke the anger of some of her own students; which could be a dangerous thing to do in Pakistan. Outside her office, I notice that students have scribbled their displeasure on a flyer for a theatre workshop in which she collaborates. Bari is thus a necessary figure in her country, a solo voice amid a choir of familiar chants.

"'Honour' for men is connected with women's behaviour because they are seen as the property of the family – and of the community," she says. "They have no independent identities, they are not independent human beings. Men also think of women as an extension of themselves. When women violate these standards, this is a direct blow to the man's sense of identity. So of course, women must inculcate these values to their children. You fail as a mother and a wife if your children don't meet these standards."

And it's not long before the word "feudal" begins to sprinkle our conversation. "Islam becomes a tool to kill only when a certain feudal system exists. You have to locate the issue in a social context. There are more "honour" killings in Pakistan than India – and in Pakistan, there have been no land reforms, there is a strong land-holding system, tribal lands are uncontrolled by the central government. It's a feudal system. There was barbarism in European history – and now some parts of Pakistan are like Europe many centuries ago. But the cruelty that happens now..." Here Bari shakes her head. "Recently, there was a pregnant woman who was suspected of having an extra-marital affair and her family set dogs on to her and she died. These are very torturing, brutal ways to kill people. I have, intellectually, a problem to explain this."

I found no one who could understand the origins of this sadism; especially as many "honour" crimes – particularly among Palestinians – appeared to be provoked by arguments over money and inheritance. The Mediterranean sloshes away outside the Gaza coffee house where Naima al-Rawagh and I meet. She oversees what she calls the Women's Empowerment Programme, a petite woman in a scarf who speaks polished English. "From my experience, it's not a religious issue, it's a cultural one," she says. Like "tribal", I'm getting a bit tired of hearing about "culture" in this context. Why not build a heritage trail between the sites of famous "honour" killings? But Naima brings me up short.

"Specific conditions in religion do not apply to the cases in Gaza. In recent years, we noticed that many women were killed because of money. A brother prefers to kill his sister to take her inheritance and then says she dishonoured the family." Frazana Bari's fellow academic in Islamabad, South Asian studies professor Tariq Rahman, seemed to be picking up the same theme – and, unwittingly, that of my own safe-box maulawi – when he wrote that "since a woman is, as it were, a treasury or a vault where men's 'honour' is stored away, she is their property. She is to be guarded, of course, but only as a box of treasure is guarded – not for itself but for what it contains."

Reflecting on this very point, Naima al-Rawagh sighs. "Believe me," she says with a sad smile, "it was better 1,400 years ago than it is now." Najdawi said something similar to me in Amman. "Our Arab, Eastern society worships a woman," he said. "The Prophet Mohamed said 'take half your religion from your wife.' After that, things went downhill in the Abbasid period, when we became more primitive. We got the hijab, the niqab..." This is almost as confusing as the explanations for the very tradition of "honour" killing. Jordanians told me it came from Palestine, from men who once owned farms and villas and who now lived, 10 to a room, in rotting camps. Others said the idea came from Egypt, but two Egyptian women insisted to me – of course – that the tradition came from Saudi Arabia.

Naima al-Rawagh says she knows of no Palestinian men who have been killed for "honour", although she tells a frightening tale of a man who wanted to re-marry five years ago. "His wife was working and she had her own financial resources and she spent all her money on him. She sent him to Egypt to buy products – but he used the money to buy a new wife. When he got back, she didn't kill him. She drugged his tea and then cut his penis off. She was put in jail. He was admitted to hospital – and died." But if this has an element of black comedy, Naima speaks of real frightfulness among the men of Gaza.

"There was a girl here who fell in love with her cousin. He had sex with her and told all his other cousins. So they went to the girl and said: 'If you don't sleep with us, we'll tell on you.' So she was raped by many of the cousins and became pregnant. Her father was very ill and she did not want him to have a heart attack. So she gave herself in marriage to one of the cousins. But the cousin will divorce her as soon as the wedding is over, because he does not know if it is his child. Someone from her family came to me for consultation. We don't give directions – we just open their eyes; they have to choose the right thing to do. I did not support this marriage – but the girl thought this would save her from these terrible rumours."

Naima, I should add, is newly married at 38. Her husband, she says, agrees there is great violence against women but thinks that women are the main cause "because they do not treat the family well". Naima says he has advised her to open a centre for male victims of violence. Naima has a Bachelor's degree in international health policy and planning from Brandeis University. Her husband is a grocery store owner.

Yet I remain perplexed. Investigating crimes of "honour" raises some disturbing questions about my own reaction to the Arab, Muslim world in which I have lived for 34 years. I have learned many things in this society which outshine our "civilised" West. I cannot fail to be impressed by the respect and care with which children treat their parents. No elderly relative is put away in a nursing home. Ageing mothers and fathers are looked after at home and die in their own beds with their families beside them. There is an instant warmth towards strangers – towards blue-eyed Westerners like me – who are invited into homes and lunched and dined with families who might have every reason to hate the lands from which they come.

Yet I also witness many less enchanting sides to this society. In the Palestinian camps, the long nights are filled with the screaming and rage of parents and children – for this is what being a refugee means, no home, no future, large families in two rooms, heat, mosquitoes, humiliation. And many children are beaten by their fathers in the Arab world – far too many; I hear of it all the time, and occasionally, sadly, I see it with my own eyes. Because this is not my land, I have to accept, socially at least, that this is a patriarchal society – which was the answer I gave to a reader who asked me why my recent massive tome on the Middle East had only 15 references for women in the index. There were also individual references to women, but I had to explain that in the Middle East it was the men who made the decisions.

I usually shy away from easy questions and answers. Why do men – and women – so often raise their voices in arguments to screaming pitch? Why is this energy used up in so furious and so worthless a manner? Oddly, it was Najdawi who, without prompting, tried to explain this when he talked about "honour". "I'm not defending 'honour' crimes," he said. "But it's the way society functions. And of course, we are very emotional people – that has been the case throughout history."

I'm not happy with this remark. We can all be emotional. And yes, in the West, jealous husbands and wives kill their spouses, even their children. But this is a system; "honour" crimes have precedents, they are set in traditions. They have a twisted, distorted reasoning behind them. "Religious men are very important in this matter," Najdawi says. "After the French Revolution, the West broke the stranglehold that religious people had on society. Unfortunately, here, we haven't managed to get rid of the hold of religious men – and the West has also reinforced our religious men because it was you, the West, that created the genie – the Taliban – in places like Afghanistan."

Like Najdawi, many of the women involved in exposing these "honour" murders as a crime against humanity remind Westerners that it is not just a Muslim phenomenon, that it should not be politicised by blaming only one region of the globe. Rana Husseini, who has written extensively on individual cases in the press and is author of a brave and shocking book – Murder in the Name of Honour – is among those in Jordan who point out that the killing of women "has occurred in several countries, among Muslims, Christians, Yazidis, Hindus and Sikhs." And most of the women I spoke to across the Middle East talked of tribal rather than religious traditions.

But the grim truth is that Westerners can no more change this – can no more persuade village elders in Afghanistan of the benefits of gender equality and an end to "honour" killings – than we could have persuaded Henry VIII of the benefits of parliamentary democracy or Cromwell of the laws of war. The height of such pomposity came the other day from Navi Pillay, the UN's High Commissioner for Human Rights. "Violent 'honour' attacks," she pontificated, "are crimes that violate the right to life, liberty, bodily integrity, the prohibition against torture or cruel, inhuman or degrading treatment, the prohibition on slavery, the right to freedom from gender-based discrimination and sexual abuse or exploitation, the right to privacy, the obligation to denounce discriminatory laws and harmful practices against women." Phew. I can see how they'll be shaking in their shoes after that in Baluchistan and Helmand province.

I am sitting on a chair in the outer room of a legal firm in Amman and a woman with a worried face, middle aged, walking slowly, passes me, head down, eyes on the floor. Is there some "honour" fear at work here too? Am I looking at another potential victim? Journalistic instinct, I guess. But Asma Khodr's office is full of light. And just inside the door, there is an old typewriter, its black and red printing ribbon still threaded through the spools, sitting atop a shelf. It belonged to Emily Bicharat, the first woman lawyer in Amman, the first president of the Jordanian Women's Union, who died four years ago. Asma Khodr is proud of this antique, and of Bicharat's role in fighting for women in a male-dominated society. Her father must have thought the same about his daughter. For on her desk stands a framed letter to a much younger Khodr, about to enter the law, from her now dead father Hanna, dated 20 December 1972.

He writes, in thin Arabic script: "Imagine you will be a lawyer defending human rights, understanding arguments and taking the side of the victims. I see you serving our homeland with a very big mind and persuading others to accept their responsibilities by your speeches of great conviction." Not a bad letter to get from your Dad, I say, and Asma Khodr laughs. And of course, I search for signs of that conviction in a woman who has also served as a minister in the Jordanian government.

"That woman you saw who was just leaving my office," she says. "She has had 20 years of marriage and there is much domestic violence – and no decent relations with her husband. And she cannot leave or run away from home in case he makes a case against her and kills her. The law here has been amended to stop this happening – but people still don't believe it."

So I was right about the middle-aged lady. But has the law changed that much? Is that woman really safe? I'm not sure I like Khodr's reply. "It is not logical to change the law at once when the values of the society are not up to that level," she says. "There must be gradual development. Yet we cannot ignore the fact that changes are going on. In our new laws, 95 per cent of court judgments are a minimum of 10 years for 'honour' crimes. Arab law is largely based on French law, which is patriarchal. No, there is nothing in the Koran for 'honour' killings, apart from lashes for adultery. Historically, stoning was a Jewish practice, afterwards used by conservative Muslims. Yes, it was patriarchal, a practice that is easy to spread. But in Middle Ages Europe, women were victims of killings because of witchcraft, were they not? The church played the same patriarchal role in those days."

We talk late into the afternoon, about the women's union, about Egypt and poverty, about religion. "The most important way of 'empowering' women" – I admit I've never liked that phrase – "is by encouraging economic opportunities," she says. "You need social justice and development to get rid of patriarchy. You cannot just rely on the law. No institutional or state powers can do all this. Some people who believe in this patriarchy are trying to exploit even God."

Then Asma Khodr says something very un-lawyerly. "I believe in the principle that human beings are pure," she says. "Crime is a product of the community. This is what you have to change. Women and men are mostly victims of this." I think she is being a bit kind to men. Yes, they are victims, but clearly they often lack the remorse or sorrow of which Najdawi spoke so mournfully.