There is an absurd scene in Palestinian writer Suad Amiry’s recent book Sharon and My Mother-in-Law that is revealing about Israeli Jews’ attitude to the two other monotheistic religions. In 1992, long before Israel turned Amiry’s home city of Ramallah into a permanent ghetto behind checkpoints and walls, it was still possible for West Bank Palestinians to drive to Jerusalem and even into Israel  at least if they had the right permit.

On one occasion Amiry ventures out in her car to East Jerusalem, the half of the city that was Palestinian before the 1967 war and has since been engulfed by relentless illegal and state-organized Jewish settlement.

There she sees an elderly Jew collapsing out his car and on to the side of the road. She pulls over, realizes he is having a heart attack and bundles him into the back of her own car. Not able to speak Hebrew, she reassures him in English that she is taking him to the nearest hospital.

But as it starts to dawn on him that she is Palestinian, Amiry realizes the terrible problem her charitable act has created: his fear may prompt him to have another heart attack. "What if he had a fatal heart attack in the back seat of my car? Would the Israeli police ever believe I was just trying to help?" she wonders.

The Jewish man seeks to calm himself by asking Amiry if she is from Bethlehem, a Palestinian city known for being Christian. Unable to lie, she tells him she is from Ramallah. "You’re Christian?" he asks more directly. "Muslim," she admits, to his utter horror. Only when they finally make it to the hospital does he relax enough to mumble in thanks: "There are good Palestinians after all."

I was reminded of that story as I made the journey to Bethlehem on Christmas Day. The small city that Amiry’s Jewish heart attack victim so hoped she would hail from is today as much of an isolated enclave in the West Bank as other Palestinian cities  or at least it is for its Palestinian inhabitants.

For tourists and pilgrims, getting in or out of Bethlehem has been made reasonably straightforward, presumably to conceal from international visitors the realities of Palestinian life. I was even offered a festive chocolate Santa Claus by the Israeli soldiers who control access to the city where Jesus was supposedly born.

Seemingly oblivious to the distressing historical parallels, however, Israel forces foreigners to pass through a "border crossing"  a gap in the menacing grey concrete wall  that recalls the stark black and white images of the entrance to Auschwitz.

The gates of Auschwitz offered a duplicitous motto, "Arbeit macht frei" (Work makes you free), and so does Israel’s gateway to Bethlehem. "Peace be with you" is written in English, Hebrew and Arabic on a colorful large notice covering part of the grey concrete. The people of Bethlehem have scrawled their own, more realistic assessments of the wall across much of its length.

Foreign visitors can leave, while Bethlehem’s Palestinians are now sealed into their ghetto. As long as these Palestinian cities are not turned into death camps, the West appears ready to turn a blind eye. Mere concentration camps, it seems, are acceptable.

The West briefly indulged in a bout of soul-searching about the wall following the publication in July 2004 of the International Court of Justice’s advisory opinion condemning its construction. Today the only mild rebukes come from Christian leaders around Christmas time. Britain’s Archbishop of Canterbury, Dr Rowan Williams, was foremost among them this year.

Even those concerns, however, relate mainly to fears that the Holy Land’s native Christians, once a significant proportion of the Palestinian population, are rapidly dwindling. There are no precise figures, but the Israeli media suggests that Christians, who once constituted as much as 15 per cent of the occupied territories’ Palestinians, are now just 2 or 3 per cent. Most are to be found in the West Bank close to Jerusalem, in Bethlehem, Ramallah and neighboring villages.

A similar pattern can be discerned inside Israel too, where Christians have come to comprise an ever-smaller proportion of Palestinians with Israeli citizenship. In 1948 they were nearly a quarter of that minority (itself 20 per cent of the total Israeli population), and today they are a mere 10 percent. Most are located in Nazareth and nearby villages in the Galilee.

Certainly, the continuing fall in the number of Christians in the Holy Land concerns Israel’s leadership almost as keenly as the patriarchs and bishops who visit Bethlehem at Christmas  but for quite the opposite reason. Israel is happy to see Christians leave, at least of the indigenous Palestinian variety.

(More welcome are the crazed fundamentalist Christian Zionists from the United States who have been arriving to help engineer the departure of Palestinians, Muslims and Christians alike, in the belief that, once the Jews have dominion over the whole of the Holy Land, Armageddon and the "End Times" will draw closer.)

Of course, that is not Israel’s official story. Its leaders have been quick to blame the exodus of Christians on the wider Palestinian society from which they are drawn, arguing that a growing Islamic extremism, and the election of Hamas to lead the Palestinian Authority, have put Christians under physical threat. This explanation neatly avoids mentioning that the proportion of Christians has been falling for decades.

According to Israel’s argument, the decision by many Christians to leave the land where generations of their ancestors have been rooted is simply a reflection of the "clash of civilizations," in which a fanatical Islam is facing down the Judeo-Christian West. Palestinian Christians, like Jews, have found themselves caught on the wrong side of the Middle East’s confrontation lines.

Here is how the Jerusalem Post, for example, characterized the fate of the Holy Land’s non-Muslims in a Christmas editorial: "Muslim intolerance toward Christians and Jews is cut from exactly the same cloth. It is the same jihad." The Post concluded by arguing that only by confronting the jihadis would "the plight of persecuted Christians  and of the persecuted Jewish state  be ameliorated."

Similar sentiments were recently aired in an article by Aaron Klein of WorldNetDaily republished on Ynet, Israel’s most popular website, that preposterously characterized a procession of families through Nazareth on Eid al-Adha, the most important Muslim festival, as a show of strength by militant Islam designed to intimidate local Christians.

Islam’s green flags were "brandished," according to Klein, whose reporting transformed a local troupe of Scouts and their marching band into "Young Muslim men in battle gear" "beating drums." Nazareth’s youngsters, meanwhile, were apparently the next generation of Qassam rocket engineers: "Muslim children launched firecrackers into the sky, occasionally misfiring, with the small explosives landing dangerously close to the crowds."

Such sensationalist misrepresentations of Palestinian life are now a staple of the local and American media. Support for Hamas, for example, is presented as proof of jihadism run amok in Palestinian society rather than as evidence of despair at Fatah’s corruption and collaboration with Israel and ordinary Palestinians’ determination to find leaders prepared to counter Israel’s terminal cynicism with proper resistance.

The clash of civilizations thesis is usually ascribed to a clutch of American intellectuals, most notably Samuel Huntingdon, the title of whose book gave the idea popular currency, and the Orientalist academic Bernard Lewis. But alongside them have been the guiding lights of the neocon movement, a group of thinkers deeply embedded in the centers of American power who were recently described by Ynet as mainly comprising "Jews who share a love for Israel."

In fact, the idea of a clash of civilizations grew out of a worldview that was shaped by Israel’s own interpretation of its experiences in the Middle East. An alliance between the neocons and Israeli leaders was cemented in the mid-1990s with the publication of a document called "A Clean Break: A New Strategy for Securing the Realm." It offered a US foreign policy tailor-made to suit Israel’s interests, including plans for an invasion of Iraq, authored by leading neocons and approved by the Israeli prime minister of the day, Binyamin Netanyahu.

When the neocons rose to power with George Bush’s election to the White House, the birth of the bastard offspring of the clash of civilizations  the war on terror  was all but inevitable.

Paradoxically, this vision of our future, set out by American and Israeli Jews, is steeped in fundamentalist Christian religious symbolism, from the promotion of a civilized West’s crusade against the Muslim hordes to the implication that the final confrontation between these civilizations (a nuclear attack on Iran?) may be the End Times itself  and thereby lead to the return of the Messiah.

If this clash is to be realized, it must be convincing at its most necessary confrontation line: the Middle East and more specifically the Holy Land. The clash of civilizations must be embodied in Israel’s experience as a civilized, democratic state fighting for its very survival against its barbarian Muslim neighbors.

There is only one problem in selling this image to the West: the minority of Christian Palestinians who have happily lived under Muslim rule in the Holy Land for centuries. Today, in a way quite infuriating to Israel, these Christians confuse the picture by continuing to take a leading role in defining Palestinian nationalism and resistance to Israel’s occupation. They prefer to side with the Muslim "fanatics" than with Israel, the Middle East’s only outpost of Judeo-Christian "civilization."

The presence of Palestinian Christians reminds us that the supposed "clash of civilizations" in the Holy Land is not really a war of religions but a clash of nationalisms, between the natives and European colonial settlers.

Inside Israel, for example, Christians have been the backbone of the Communist party, the only non-Zionist party Israel allowed for several decades. Many of the Palestinian artists and intellectuals who are most critical of Israel are Christians, including the late novelist Emile Habibi; the writer Anton Shammas and film-makers Elia Suleiman and Hany Abu Assad (all now living in exile); and the journalist Antoine Shalhat (who, for reasons unknown, has been placed under a loose house arrest, unable to leave Israel).

The most notorious Palestinian nationalist politician inside Israel is Azmi Bishara, yet another Christian, who has been put on trial and is regularly abused by his colleagues in the Knesset.

Similarly, Christians have been at the core of the wider secular Palestinian national movement, helping to define its struggle. They range from exiled professors such as the late Edward Said to human rights activists in the occupied territories such as Raja Shehadeh. The founders of the most militant wings of the national movement, the Democratic and Popular Fronts for the Liberation of Palestine, were Nayif Hawatmeh and George Habash, both Christians.

This intimate involvement of Palestinian Christians in the Palestinian national struggle is one of the reasons why Israel has been so keen to find ways to encourage their departure  and then blame it on intimidation by, and violence from, Muslims.

In truth, however, the fall in the number of Christians can be explained by two factors, neither of which is related to a clash of civilizations.

The first is a lower rate of growth among the Christian population. According to the latest figures from Israel’s Bureau of Census Statistics, the average Christian household in Israel contains 3.5 people compared to 5.2 in a Muslim household. Looked at another way, in 2005 33 percent of Christians were under the age of 19, compared to 55 percent of Muslims. In other words, the proportion of Christians in the Holy Land has been eroded over time by higher Muslim birth rates.

But a second factor is equally, if not more, important. Israel has established an oppressive rule for Palestinians both inside Israel and in the occupied territories that has been designed to encourage the most privileged Palestinians, which has meant disproportionately Christians, to leave.

This policy has been implemented with stealth for decades, but has been greatly accelerated in recent years with the erection of the wall and numerous checkpoints. The purpose has been to encourage the Palestinian elite and middle class to seek a better life in the West, turning their back on the Holy Land.

Palestinian Christians have had the means to escape for two reasons. First, they have traditionally enjoyed a higher standard of living, as city-based shopkeepers and business owners, rather than poor subsistence farmers in the countryside. And second, their connection to the global Churches has made it simpler for them to find sanctuary abroad, often beginning as trips for their children to study overseas.

Israel has turned Christian parents’ financial ability and their children’s increased opportunities to its own advantage, by making access to higher education difficult for Palestinians both inside Israel and in the occupied territories.

Inside Israel, for example, Palestinian citizens still find it much harder to attend university than Jewish citizens, and even more so to win places on the most coveted courses, such as medicine and engineering.

Instead, for many decades Israel’s Christians and Muslims became members of the Communist party in the hope of receiving scholarships to attend universities in Eastern Europe. Christians were also able to exploit their ties to the Churches to help them head off to the West. Many of these overseas graduates, of course, never returned, especially knowing that they would be faced with an Israeli economy much of which is closed to non-Jews.

Something similar occurred in the occupied territories, where Palestinian universities have struggled under the occupation to offer a proper standard of education, particularly faced with severe restrictions on the movement of staff and students. Still today, it is not possible to study for a PhD in either the West Bank or Gaza, and Israel has blocked Palestinian students from attending its own universities. The only recourse for most who can afford it has been to head abroad. Again, many have chosen never to return.

But in the case of the Palestinians of Gaza and the West Bank, Israel found it even easier to close the door behind them. It established rules, in violation of international law, that stripped these Palestinians of their right to residency in the occupied territories during their absence. When they tried to return to their towns and villages, many found that they were allowed to stay only on temporary visas, including tourist visas, that they had to renew with the Israeli authorities every few months.

Nearly a year ago, Israel quietly took a decision to begin kicking these Palestinians out by refusing to issue new visas. Many of them are academics and business people who have been trying to rebuild Palestinian society after decades of damage inflicted by the occupying regime. A recent report by the most respected Palestinian university, Bir Zeit, near Ramallah, revealed that one department had lost 70 per cent of its staff because of Israel’s refusal to renew visas.

Although there are no figures available, it can probably be safely assumed that a disproportionate number of Palestinians losing their residency rights are Christian. Certainly the effect of further damaging the education system in the occupied territories will be to increase the exodus of Palestine’s next generation of leaders, including its Christians.

In addition, the economic strangulation of the Palestinians by the wall, the restrictions on movement and the international economic blockade of the Palestinian Authority are damaging the lives of all Palestinians with increasing severity. Privileged Palestinians, and that doubtless includes many Christians, are being encouraged to seek a rapid exit from the territories.

From Israel’s point of view, the loss of Palestinian Christians is all to the good. It will be happier still if all of them leave, and Bethlehem and Nazareth pass into the effective custodianship of the international Churches.

Without Palestinian Christians confusing the picture, it will be much easier for Israel to persuade the West that the Jewish state is facing a monolithic enemy, fanatical Islam, and that the Palestinian national struggle is really both a cover for jihad and a distraction from the clash of civilizations against which Israel is the ultimate bulwark. Israel’s hands will be freed.

Israelis like Amiry’s heart attack victim may believe that Palestinian Christians are not really a threat to their or their state’s existence, but be sure that Israel has every reason to continue persecuting and excluding Palestinian Christians as much, if not more, than it does Palestinian Muslims.