A world of false frontiers Walls: Travels Along the Barricades, by Marcello Di Cintio, Union Books, RRP£14.99, 288 pages Human civilisation has always been preoccupied with erecting walls," Marcello Di Cintio points out in his illuminating, brilliantly composed book, Walls: Travels Along the Barricades. Hadrian built a 120km-long limestone wall across Roman Britain; the Chinese built the Great Wall. Not much seems to have changed from those ancient times, as Di Cintio discovers when he travels to eight different countries that have built walls. These include his native Canada where in 1960 the city of Montreal built L'Acadie Fence, a 2m-high chain-link fence separating one of the city's most affluent areas from one of its poorest neighbourhoods. He points out that all these walls, with the exception of the one in the Western Sahara - built by Morocco and manned by its troops - do not serve their intended purpose; whether as barriers against violence, smuggling or illegal immigration. The question - one I have often asked as I drive along Israel's 8m-high barrier at Kalandia, north of Jerusalem, which separates Palestinian homes in the West Bank from each other - is why do countries continue to waste billions of dollars on such apparently useless projects? One answer that Di Cintio proposes is that walls are works of theatre. Scholars still wonder, he tells us, whether Hadrian's Wall had any utility "beyond a theatrical expression of imperial power." The wall was a spectacle: "Plastered and whitewashed, the Wall would have shone for miles beneath the northern sun." Likewise, the $4bn barbed-wire barrier along the India-Bangladesh border does not, as Di Cintio points out, "deter unwanted Bangladeshis from crossing the "zero line"." Why, then, was it built? According to the Indian economist Jagdish Bhagwati: "building the fence was the least disruptive way of doing nothing while appearing to do something." Di Cintio writes that it served as an "illusion to soothe an anxious nation." In other words, a therapeutic spectacle. Walls also divide, and in the case of the one along India's frontier, it imposes a uniform national identity, an "Indianness" where there was none before. The wall "christens the villagers Indians and warns them that those on the other side are not." In Ceuta and Melilla, Spanish enclaves in northern Africa, Di Cintio found that the walls embodied old notions of identity: ""We are different from the Moors," the Spaniards cry, and the walls prove this." Di Cintio concludes that these walls stand "less as security barriers than as monuments to Spanish insecurity." The same could be said of the walls in Israel and those erected in Belfast - despite the latter's misnomer of "peace line," bestowed in 1969 by Belfast's first wall-maker, the British army chief of the time, Sir Ian Freeland. His soldiers erected the first section in 1969: "a line of barbed wire to separate Protestant and Catholic rioters" along Cupar Way. Travelling to Cyprus, Di Cintio finds that the walls in Nicosia separating the Greek Cypriots from the Turkish-controlled areas force identities on those who cannot cross them: you are either from here or from there. Either one of us or one of them. For those, like the author, who are fortunate enough to be able to cross over, the walls create two sides - and you have to take one of them. But not all walls mark such precise separations. The West Bank wall does not create a definitive division between Israel and Palestine. There are Israeli settlers living on the Palestinian side of the wall as there are Palestinians living on the Israeli side. What, then, was the purpose of the wall? Undoubtedly it has an element of a spectacle and has given some Israelis a sense of security, even though it was not the wall that stopped the dreaded suicide bombings. That happened largely because of a change in tactics on the part of Hamas, which launched them. The wall, built mainly inside the West Bank, does serve as a means of grabbing more Palestinian land. But it has another purpose. It provides Israel with a new means of exercising control after it transferred to the Palestinian Authority many of the civilian powers it held before the Oslo Accords were signed in 1993. Now, as Di Cintio discovers, Israel can choose which Palestinians will be granted permits to cross to Israel for work, to pray in the al-Aqsa Mosque or to visit relatives in East Jerusalem. Di Cintio's book is a travel book that takes its readers through many countries and gives them a sense of what it is like to live on one side of a wall and to experience the fragmentation and destruction of the landscape of one's country. He writes with passion and empathy for the victims of those monstrous walls that take no account of how they affect the human beings living next to them. Nor does he shy away from expressing outrage. In Nicosia, after trying to coax a friend to cross the wall to the Turkish side, the author realises the limit of what he, as on outsider, can experience, concluding that "as much as I learn about the walls and as much as I try to empathise with those who inhabit their shadows, the truth remains that the walls are not meant for me. I don't have the right to coax anyone across. Whether walls are a spectacle, a form of theatre or a marker separating "us" from "them," the civilised from the barbarians, they are not a neutral object but have a subjective effect. Not only do they divide, they can make those living in their shadow physically ill - as I know from experience, living as I do in the shadow of a wall. Di Cintrio mentions the East German psychiatrist Dietfried Müller-Hegemann, who observed in 1973, "when the Berlin Wall was still standing that it caused psychosis, schizophrenia, and phobias in the East Germans who lived in its shadow. They suffered rage, dejection, and alcoholism - and were more likely to kill themselves. The closer to the physical wall his patients lived, the more acute their disorders. Sometimes the emotional trauma expressed itself in the flesh ... The only cure for the Wall Disease was to bring the Wall down. Di Cintio has identified the common symptoms of a prevailing sickness afflicting many countries, causing them to resort to building expensive but useless walls that are so destructive to the landscape and so harmful to the people living next to them. Nature, of course, has its own cure; eventually the desert, as he writes "will forget the wall." What is doubtful is whether those whose lives have been shattered, or who are forced to live in exile, will ever forget. Yet if, in revealing the folly of building walls, his book, which won the Shaughnessy Cohen Prize for Political Writing, helps to stop the spread of this affliction, it will have served a great purpose. Raja Shehadeh is a lawyer and writer living in Ramallah, West Bank. His most recent book is "Occupation Diaries" (Profile)