GENERATIONS of teenagers attending the College Condorcet, not far from the Gare St Lazare in Paris, have loitered outside on the corner of the rue d'Amsterdam and the rue de Bucarest, waiting for the bell to signal the start of classes, chattering, pushing each other, pulling on final, illicit cigarettes.
But these days they have been ordered to wait inside the school building. Trips by Metro to the Bois de Boulogne for sport are off. They go in a hired coach, or exercise in the school yard.
After six bombs and attempted bombings in three months the education system - like the rest of the capital - is on red alert.
A mile or so away in the rue de la Victoire, car-owners have seen some of their rare residents' parking spaces blocked off by metal barriers; there is a primary school in the street and no parking is allowed within a dozen metres of the gate.
Paris used to be one of Europe's cleaner capitals. Now papers, soft drink cans and other litter disfigure streets and Metro stations after the sealing or removal of rubbish bins in areas considered likely targets.
The first and bloodiest attack in the wave of bombings killed seven people at the Saint-Michel RER (express undergound) station on 25 July. A device exploded in a litter bin near the Arc de Triomphe in mid-August, injuring 17 people; another hidden in a pressure cooker injured four at an open- air market early in September, while a bomb timed to explode at the same time at another market failed to go off.
This month there was an explosion at a Metro station to coincide with the funeral of the young Algerian terrorist suspect, Khaled Kelkal, killed by police. On Tuesday a second attack on the RER injured 29 people.
Superficially,Parisians seem to be taking the terrorist campaign in their stride. The Champs-Elysees are as busy as ever and restaurants are full. There are long queues for the latest Gerard Depardieu film.
Parisians have been here before. During the 1980s there were sporadic attacks, often against Jewish targets. In 1986, a particularly black year, there was a series of blasts, including the bombing of a clothes shop which killed seven people.
Most of those attacks had a Palestinian or Middle East dimension. Carlos the Jackal, now in prison in France awaiting trial, was allegedly involved in at least some of them.
The capital has always been heavily policed, but to meet this latest wave of attacks security has been massively and obviously increased. Under the Vigipirate emergency scheme hundreds of extra men and women are on the streets, including some troops. A bus full of CRS paramilitary police is parked under the Eiffel Tower and the nearest RER station is intensively patrolled.
But on another level the campaign is beginning to take its toll. "Yes, I'm worried," said a waitress in a restaurant not far from the Champs- Elysees.
"This morning there was a bag under a seat in the Metro and I asked the woman sitting on the seat if it was hers. You can't be too careful."
At the autumn fashion shows even the most distinguished of guests were frisked. Security staff in shops and other public places check bags, even though the bombers' pattern is well established: they use gas cylinders or other metal containers packed with nuts and bolts to act as a kind of shrapnel.
Such packages are not easy to hide and may explain why the RER, where the carriages are often double-deckers and partitioned, has been chosen over the more open-plan Metro.
Hoaxes and false alarms add to the feeling of insecurity. Hundreds of police identity checks are carried out daily. Newspapers carry telephone numbers of clinics offering counselling for those affected by bombs.
Wealthy, conservative Paris is psychologically a world away from the new towns and dormitory suburbs that closely ring it.The Algerian and other North African communities have their enclaves in the city itself, most noticeably in the Barbes-Rochechouart area. But Parisians' contact with the Algerian com munity, apart from the owners of small late-opening mini-markets, is relatively limited.
Now they have to come to terms with the arrival in their city of the shockwaves of the savage civil war in Algeria and the danger that the anger, frustration and resentment of young Arabs is being channelled into a radical and lethal fundamentalism.
There were fears during the Gulf War that the millions of North African first and second generation immigrants might provide a reservoir of sympathy for Saddam Hussein. In the event there was no sign of any significant support for him.
But this time things may be different. Mouloud Aounit, secretary-general of the anti-racist group Mrap, fears that the terrorist campaign is having a dangerous effect on race relations. He says previously undecided people are becoming more receptive to the poisonous xenophobia of the National Front.
"The Algerian community is closing in on itself; there are fewer openings to the rest of French society. And police identity checks based on the colour of your skin are alienating still further the young."
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