LEADING ARTICLE : The lessons of Oklahoma

More than 24 hours after the bomb in Oklahoma it is still not yet clear who was responsible for the outrage, but circumstantial evidence points to an Islamic terrorist group. The United States has plenty of enemies across the entire Muslim world. Yet it has had such enemies for the past two decades, but they have only recently carried their war on to US soil. So what has changed?

In the past, such terrorists found it easier to attack US embassies abroad or to seize American citizens there. The logistics of working in the distant United States were more tricky. More significantly, mainstream Palestinians restricted the activities of such extremists; Yasser Arafat, according to Western intelligence agencies, co-operated with the CIA through the Eighties to hinder acts of terrorism.

Things are different now. Today's terrorist factions are more fragmented and more dangerous than before. Had the World Trade Center bomb in 1993 been better placed, or had the plane hijacked in Algiers crashed on Paris, as planned last Christmas, their impact would have been quite terrifying. The choice of Oklahoma as a target indicates increasing sophistication. To blast away an ordinary government building in the heart of America will have a lasting effect on the national psyche. Beirut has come to the backyard.

It would be easy to say that Americans - never bombed, apart from Pearl Harbor - have failed to understand terrorism, exploiting it where it suited foreign policy objectives, or bestowing upon it facile endorsement, as in the case of Gerry Adams. But it was scarcely constructive yesterday for Tory backbenchers to round on President Clinton and demand that he now justify his support for Sinn Fein.

What can be said that is constructive? The most immediate sentiment is a plain and deeply felt sharing of America's grief. Too many Europeans know only too well what is like to have the heart blown out of their cities and the sense of helplessness which arises from a ruthlessly conducted campaign of terror. Here, the IRA's war is in ceasefire rather than definitively over; in Germany the Baader-Meinhof gang may be consigned to history but random assassinations of public figures still occur. In Spain this week the leader of the main opposition party narrowly escaped death at the hands of the Basque separatist movement.

The lesson is that there are no quick answers. Effective intelligence counts - that is how European secret services thwarted the terrorist backlash expected during the Gulf war. Security systems can also make an impact; there were no incidents in the City of London after a police cordon was thrown around it following the Bishopsgate bomb.

But in the end the only long-term solutions are political.That means the United States maintaining its sense of engagement with the world, no matter how slippery the Middle East peace process becomes, no matter how complex and unpalatable the choices that arise - for example, in adopting a coherent position on the murderous politics of Algeria. At home, America will need ways of drawing into public debate those groups which feel estranged, whether they be mixed-up teenagers, bizarre religious cults or politically deprived communities. What is not needed is precipitate feel-good retribution against whichever country comes to the top of the FBI's list of suspects. Americans are, alas, at the opening stage of a long, bitter and frightening war.