Leading article: The war of intelligence

In all of this, there was hyperbole. The response of the people of London to the horror of the carnage on crowded Underground trains and a packed bus was one of impressive and measured defiance. The emergency services deserve unreserved gratitude for their professionalism, and the thousands of acts of heroism by doctors, nurses, ancillaries and members of the public were a tribute to the solidarity of such a large and usually anonymous city. Yet it is easy to overstate the extent to which the bombers were answered by a display of Great British grit: many people had no choice but to walk for miles on Thursday, and cancelmania took a firm grip, at least of the public sector, on Friday.

It was a week in which the Prime Minister's qualities of leadership were tested. Tonally, he met the fluctuating mood of the moment perfectly. He avoided triumphalism when the result of the Olympics vote was announced; his unfailing courtesy was all the rebuke that Jacques Chirac needed for his rudeness about British agriculture. And unlike some of the more excitable pop stars, he avoided overclaiming his achievement at Gleneagles on Africa. He was similarly downbeat about the deal on climate change, recognising that US engagement and pressure on George Bush offer the only hope of progress.

Above all, however, he realised immediately the seriousness of what had happened in the capital and was able to give expression to the national mood of shock and solidarity that followed the four bombs. Inevitably, there are those, such as Dilip Hiro (see page 30), who hold the Prime Minister indirectly responsible for the bombing. It was certainly one of this newspaper's arguments against joining the invasion of Iraq that it would increase rather than diminish the global terrorist threat. But we accept that British troops should not have been withdrawn from Iraq after the invasion and should not be withdrawn now. As such, we have to face the terrorist threat squarely.

That means focusing relentlessly on intelligence and police work. Just as we should not be carried away by the emotion of the wartime spirit, so we should not allow politicians to use any overreaction in public sentiment to bring in more bad legislation on the back of another terrorist outrage. In the wake of the Omagh bombing in 1998, Tony Blair rushed emergency legislation through the Commons that was never used. There was a similar rush to bad law - eventually struck down by the Law Lords - after the attacks on America in 2001.

It ought to be said, however, that both Mr Blair and Charles Clarke, the Home Secretary, seem admirably reluctant to exploit populist fears this time. Mr Clarke said plainly that identity cards would not have helped prevent the attacks, although that might be going too far, because we simply cannot know at this stage. But it offers a welcome contrast with what the volatile David Blunkett might have said had he still been at the Home Office.

In general terms, however, Mr Clarke is clearly right. It is difficult to see what additional powers ministers need after the encroachments on the freedom of citizens in recent years. And as Mr Blair rightly said, if terrorists are prepared to go on a Tube or a bus and blow up people at random, "you can have all the surveillance in the world and you couldn't stop that happening". Certainly, creating a new offence of glorifying or condoning acts of terrorism, which is said to be under consideration for a new anti-terrorism Bill, seems utterly beside the point.

Once again, Mr Blair is compromised by his closeness to President Bush. The simplicities of the "war on terror", an implausible military struggle against an abstract noun, have warped much of the effort to contain and counter the threat from al-Qa'ida and its spawn. One of the side-effects of such inapt language has been to foment complacency. Because the war on terror seemed to be fought largely on the streets of Baghdad - suffering the equivalent of what happened in London every few days - the terrorist threat to Western cities appeared distant.

Last week was an important reminder of the real priorities. They remain intelligence and police work, rather than new powers of surveillance and control or counterproductive military action to "suppress" terrorists at source. As Professor Aldrich observes overleaf, the "new" terrorism has turned out to be not so new after all. It does not appear to be indiscriminate, or to be aimed simply at maximising death and destruction. On the contrary, it seems to be highly political and targeted.

Two things, however, are new, and, in combination, make it particularly hard to defend against. One is the context of global travel and communications, and the other is the potential for the use of suicide as a weapon, although the evidence so far as to whether the London explosions were caused by suicide bombers is mixed.

The resolute response of both the British public and the Prime Minister to Thursday's horror sets the right tone for policy to minimise the risks in the future. Despite the horror, we should be relieved that the death toll was so low. But equally we should be alert to the potential for it to be so much higher next time.

It should now be clear that those people who accused the Government of exaggerating the threat of terrorism in order to get illiberal legislation on to the statute book were tilting at the wrong target.

Equally, however, it should be clear that further attempts to remove historic protections of liberty and justice are irrelevant to the real need, which is for patient investigation, and, in both senses of the word, intelligence.