A FEW weeks back, I wrote a piece that mentioned the security fence between Israel and the West Bank. My article was an attempt to articulate how (mostly) left-wing Israelis, perplexed by the collapse of negotiations with the Palestinians and desperate to escape the daily suicide attacks, were promoting the fence as a sort of unilateral disengagement from the Palestinian territories. Very reluctantly, Ariel Sharon was being forced to adopt the policy, despite vigorous resistance from the Israeli right wing.

Alas, there is a sad tendency among those who disagree with the fence to attack anyone trying to explain it as personally complicit in its alleged failings. Thus, the Scottish Palestinian Solidarity Campaign (SPSC) website devoted space to a lengthy diatribe against my article, penned from Tulkarm on the West Bank. In the spirit of democratic debate, the SPSC called me a "hack" and "the Barclay brothers’ liar in chief". "What condensed callousness drips from Kerevan’s keyboard," exclaims the writer. According to this polemic, the fence "is a prison for Palestinians" and "Kerevan must lack the simplest ability to consult a map. Why does The Scotsman employ such cartographically-challenged individuals?"

Today the International Court of Justice begins formal hearings into the legality of the barrier.

	No cause in the world justifies the extremists penchant for blowing up school buses.

No-one can doubt the fact that, whatever the original motives behind building it, the fence has become yet another irritant in the long-running dispute between Israelis and Arabs in the Holy Land. From the Palestinian perspective, the fence is seen as a land grab because it takes in areas that were inside the West Bank before Israel occupied these territories during the Six Day War in 1967.

Having lived through the Troubles in Northern Ireland, where my mother was caught in several bombings, I am only too well aware of the ease with which two sides can misconstrue each other’s motives. I am also well aware that there are always people who want to make mischief. For instance, the author of the Tulkarm venom is actually a prominent Scottish left-winger. For him, Palestine is just another cause to hijack in his ceaseless war against capitalism.

Nevertheless, let me have one more try at shedding a little light on the issue of the security fence. Try grasping this one essential fact: far from being an Israeli plot, the damn thing is a giant piece of improvisation. Two and a half years ago, practically no-one in Israel wanted it. For one thing, it is horrendously expensive to build and the Israeli economy is in tatters, thanks to the dotcom meltdown and the intifada. Besides, Israel’s extreme right has never been comfortable with giving up West Bank and the thought of marooning Jewish settlements behind a barrier is anathema to them.

The impetus to build the fence came in March 2002 after 37 attempted Palestinian suicide bombings were launched in 31 days. I found wandering around Belfast in the 1970s was nerve-wracking enough, but at least you knew the Provos would try to give a warning before a bomb went off. In Israel, as we saw again on Saturday, the aim of Palestinian extremists is deliberately to murder civilians. In particular, they have a penchant for blowing up school buses - I’m sorry, but I find no cause in the world justifies such "condensed callousness".

The Israelis found themselves in a bind. Something had to be done to stop the suicide bombings. Yasser Arafat’s Palestinian Authority showed no capacity or inclination to curb the extremists on its own side. Arafat is no Nelson Mandela, which is Palestine’s tragedy. Rather than use his standing in the Arab world to lead from the front, he has maintained his position by playing off the various Palestinian factions against each other. Thus, on Saturday, his Palestinian Authority was condemning - in words - the suicide bomb in Jerusalem. But responsibility for the attack was claimed by a section of his very own Fatah movement, the al-Aqsa Martyrs Brigades.

With no other option other than massive repression on the West Bank, the Israelis have opted to keep out the suicide bombers by starting to build the security fence. Just for the record, I know that, in places, it is a cement wall rather than a wire fence: this tends to be in areas where there has been sniping from the Arab side. There is a similar wall in Belfast, built to stop the communal violence. To date, no-one has referred the Belfast wall to the International Court of Justice.

Is the Israeli fence "illegal"? This is a daft question because the answer - whatever it be - is beside the point. Israeli bashing is not going to restart negotiations and the Israelis are certainly not going to take the fence down until the suicide bombings cease. The Palestinians may secure a propaganda victory, but where does it get them in practical terms?

That said, it seems to me the Israelis have a right to protect themselves. Some, such as the Liberal Democrats’ foreign affairs spokesman, Sir Menzies Campbell, pay lip service to this, but then say the fence should not be "on land earmarked for a Palestinian state". Sir Menzies even wants the European Union to withdraw preferential trading terms with Israel until it complies. This is disingenuous. Just how do we get into negotiations to determine the borders of Palestine until the suicide bombing is stemmed? And how do we stop the suicide bombing without the fence?

The case for the fence’s illegality rests on the notion that Israel is illegally "occupying" the West Bank. For the sea lawyers among you, remember the West Bank was originally a part of Jordan and not Palestinian. In 1967, it was Jordan that attacked Israel first - the Israelis were at war with Egypt and Syria at the time and wanted no unnecessary fight with the Jordanians in their back yard. Israel then overran the West Bank in self defence. There is nothing illegal I can see in a state, in such circumstances, taking appropriate security measures on captured territory until such time as there is a general settlement.

Does the fence inconvenience Arabs disproportionately? Yes, and the Israelis need to rethink its line in places. But even more inconvenience has been caused to the 135,000 Palestinians who used to work freely in Israel but have lost their jobs because the suicide bombers have blown up the economy and created a security nightmare. The fence just might ease their predicament.

The key issue is whether Israel is prepared to move the fence when a border is recognised with an independent Palestine. We can all call Ariel Sharon names, but let’s look instead at the facts. Israel has a proven history of taking down security fences - it did so in South Lebanon and the Sinai. Israel has said it does not consider the fence the final border with Palestine and is willing to negotiate a land swap. Clearly, the Palestinians want the 1948 border (the so-called Green Line). Equally clearly, the Israelis want to give up land in the Negev in return for ironing out twists in the Green Line.

That’s all for negotiation. But does anyone doubt that if, instead of suicide bombers, Yasser Arafat had led non-violent, sit-down strikes on the Green Line, such negotiations would not be further forward today?