Protecting long-standing British liberties, while equipping ourselves against Al-Qaeda, is one of the greatest political dilemmas facing us today. How do we remain a liberal society at a time of heightened public fear?

The government’s initial response in the aftermath of the 9/11 attacks was to introduce a volley of new anti-terror laws, some of which were good, many of which need revisiting. Tony Blair, and John Reid as his last home secretary, indulged in spine-chilling rhetoric about the terrorist threat, in part to justify their legislative hyperactivity and to crush any concerns about the effect on British civil liberties and due process.

Thankfully, the tone of the political debate is now starting to change. Gordon Brown and Jacqui Smith appear to have abandoned much of the breathless Blairite rhetoric. But on substance they appear determined to pursue exactly the same legislative course.

So this autumn will be an important test for all parties, especially the government, to demonstrate their ability to forge a national consensus on terrorism, and to strike the right balance between our liberties and our safety. I believe progress can be made in three areas.

First, we must engage in the ideological debate. Liberalism is the very essence of what the terrorists seek to destroy and so must be the starting point of our own defences. Al-Qaeda-inspired Islamist extremism seeks to overturn democracy, destroy the distinction between religion and government, oppress women, and eliminate individual choice in the name of an unforgiving God.

Our aim must be to refute the medievalism of Al-Qaeda’s perverted world view, while ensuring that members of our mainstream Muslim communities feel that our liberal values of tolerance and diversity are their values too. We must combine critical engagement with the many grievances held among mainstream Muslims, without necessarily accepting them, drawing a clear red line beyond which liberal respect for other views does not extend.

This ideological engagement has hardheaded security objectives: no terrorist movement in history has been defeated without first winning over the wider community in which extremism can be given tacit support and camouflage. Here, the Muslim Contact Unit of the Metropolitan police has pioneered a model strategy of engagement with Muslim groups.

Second, we should look again at the design of our counter-terrorism institutions. The division between our domestic intelligence agency (MI5) and our foreign intelligence agency (MI6) was designed before the nature of global terrorism blurred the line between the two. What happens in Pakistan or Afghanistan directly impacts upon life in Bradford or Sheffield. The global reach of the terrorist threat makes a mockery of any neat division of labour between domestic and foreign intelligence.

Some have suggested a complete merger of MI5 and MI6. This would be a mistake. Instead those parts of MI6 which already work closely with MI5 should integrate into joint sections. This would formalise arrangements, ensuring there is no slippage in MI6’s ability to achieve its valuable work promoting British interests and gathering intelligence abroad.

We should revisit the organisation of police antiterror operations too. Currently London’s Metropolitan police has “lead responsibility” for terrorism across the country. But the sources of home-grown terror threats are not confined to London. So it is only logical to transform the Met’s national role into a fully fledged national counter-terrorism service leading a UK-wide approach.

Finally we need to make it easier to bring prosecutions against terror suspects. The government has invested enormous energy in devising new measures which bypass the due process of our courts, such as extended detention without charge and control orders.

Due process and the rule of law have protected us for centuries. They should not be sacrificed now. That is why the government should explore a number of changes which will make it easier to bring terror suspects to British courts: allowing the Crown Prosecution Service to bring charges even when there is a delay in producing all the evidence; the use of postcharge questioning, with appropriate safeguards, when there is a need to obtain further information. The use of “plea-bargaining” should be used more in terrorism cases so that suspects on the edge of terror plots are encouraged to provide intelligence on terror masterminds. Intercept evidence should be made admissible in court.

Taken together these measures would represent a powerful strengthening of our ability to bring terrorists to justice. They go with the grain of our own legal traditions and safeguards and would avoid a fruitless parliamentary spat on the further extension of the 28-day period during which suspects can be held without charge. The fact that Gordon Brown is determined to make this the centrepiece of his antiterror package, without producing compelling evidence of its necessity, suggests he is just as susceptible to political grandstanding on terrorism as his predecessor.

As the national debate on terrorism matures, our aim should remain steadfast and simple: to protect both our lives and our liberties, and to refuse to accept that one requires the sacrifice of the other.

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