Terrorists and what they may or may not be capable of dominated the news agenda again last week. Extra security measures at stations were announced, which mean hundreds of thousands of commuters will face a daily reminder of what ghastly fate they may meet if Al-Qaeda gets its way.

Meanwhile, the Commons home affairs committee was considering more proposed antiterror legislation, including extending the maximum period of 28 days during which a suspect can be detained without charge. As a survivor of the 7/7 bombings, I was asked to give evidence.

Monstrous as the atrocities of 7/7 were, I am not sure that we need to react as we are doing. Terrorism likes publicity. If I were Al-Qaeda’s UK PR officer, I’d be rather pleased with last week’s excellent coverage, especially given the material I had to work with over the past few months. Limousines full of gas canisters that could be unwittingly towed right across London by parking staff without exploding? Glasgow airport under threat by men so inept that one set fire to himself while trying to throw a Molotov cocktail before being thumped to the floor by a passer-by? A weeping shopgirl who admitted that she changed her nickname from “Lyrical Babe” to “Lyrical Terrorist” because she thought it sounded “cool” and hoped to find radical romance online?

A video was shown at the trial last week of defendants accused of terror offences filmed on a “training weekend”, gamely trying to leap a stream commando-style and repeatedly falling in – to howls of mirth from the public gallery. Not quite the lethal mujaheddin hordes of nightmares. Scary? Or just a very British collection of bloody-minded bungling amateurs?

Yet you do not need to be especially clever, or cunning, to be useful to the terrorist cause. You need to be idealistic, angry, reckless, committed, useless at long-term thinking, gullible and easily manipulated. There are an awful lot of people who fit into that category. In fact, if you don’t fit into that category at some point between 15 and 25, you are likely to be something of an oddity, whatever your religion or background.

Germaine Lindsay, who suicide-bombed the Underground carriage I was travelling on two years ago, was 19 years old when he died, killing 26 innocent people and injuring 100. His fellow bomber, Hasib Hussain, who blew himself up on the No 30 bus, killing 13 passengers and injuring scores, was 18 years old. They were ordinary British teenagers, motivated, the official government narrative says, by “a fierce antagonism to perceived injustices by the West against Muslims and a desire for martyrdom”.

It is worrying that Samina Malik, the 23-year-old self-styled “Lyrical Terrorist” now awaiting sentence, believed that her vicious outpourings and habit of watching beheading videos on the internet made her appear “cool”. Yet when we give such prominence to the terrorist threat that we consider handing over ancient freedoms – not to be detained without charge, submit to conversations and e-mails and movements being tracked and watched and logged and agree not to gather in peaceful protest – we show our fear and prop up the self-important fantasies of the terrorists.

The youngster with a backpack of homemade explosives versus the mighty power of the state is a potently empowering image of rebellion for disaffected youth. There are hundreds of thousands of disaffected Saminas. Youthful posturing, secretiveness, obsessive internet surfing, writing angry poetry and expressing a desire to die because “nobody understands” your pain can fast-track into real chaos and carnage.

I wonder whether we are in danger of helping to glamorise the thing we despise, as well as demonstrating to those who seek to destabilise us and who despise our tolerance and our freedoms that scaring us makes a real difference to our behaviour. Extremist attitudes are very far from “cool”; having read some extremist literature recently I was struck by how paranoid, rambling, racist and antisemitic it is. Its intention is to create a kind of theocratic prison state: I doubt Samina would be pouting in her glittery hijab and her tight jeans in an extremist theocracy.

In Westminster more antiterror legislation is under way. I told the committee that I was against extending the 28-day detention period. No evidence had been put forward to show that it was necessary and while the police and security services said they thought it might be useful in future, I did not think that was sufficient grounds for shredding habeas corpus.

The government talks of the new complexity of terrorist plots, but MI6 officers confirm that for years they have worked with police and security services around the world to combat organised crime such as international drug or weapon trafficking operations that involve networks of suspects in different countries. Such cases involve evidence cached on computers, hours of surveillance and intercept evidence to go through and some of the best resourced, most determined criminal masterminds. Why is terrorism so different? Isn’t terrorism organised crime, with a side order of propaganda and theology?

There is no proof that the availability of lengthy detainment without trial would have stopped the 7/7 bombers or the 21/7 bombers or any of the other failed bomb plots of the past few years. Legislating on the basis of what might happen, accumulating powers “for the future”, has no place in British democracy.

In 1940, faced with the threat of German invasion, Churchill brought in regulation 18b. This gave the government the power to detain anyone it thought was a threat to national security without charge or trial. Churchill loathed it and said that to detain a man “without the judgment of his peers is in the highest degree odious and the foundation of all totalitarian government, whether Nazi or communist”.

More than a thousand suspected fascists were locked up, although none was ever shown to be a genuine threat. All detainees were released before the end of the war and 18b was effectively abandoned.

Nothing convinces me that we face anything like the threat to daily life and liberty that we did in the 1940s. The only possible explanation for this recent desire for 58 days’ internment without charge is that it is politically motivated. Since 7/7 I have spent a lot of time talking to the police and security services and it has become clear to me that it is not being pushed by them.

The sudden capitulation of Lord West, who was unconvinced of the necessity to extend the 28-day limit on Radio 4’s Today programme the other morning but changed his mind after half an hour in Downing Street, proves this point. This is the politics of fear and it is a disgrace.

Both the Conservative and Liberal Democrat shadow home secretaries have spoken out powerfully against the government’s plans. I never thought that I would have much to discuss with a Conservative shadow home secretary, but I am meeting David Davis in the next few weeks and I will be interested to learn whether the Tories, if elected, would repeal some of the worst laws made in the name of terror.

Meanwhile, terrorists continue to rely not on the bang but on the fear of the bang. Terrorists desperately want politics and the media to notice them. By showing we are so rattled that we will give up our cherished liberties, we are giving those with murderous jihadi dreams a gift. By pandering to the toxic fantasies of suburban wannabe warriors, by dignifying their delusions of global struggle with horrified headlines and constitutional change, we are debasing what we stand for.

Rachel North is the author of Out of the Tunnel, a memoir. Her blog is www.rachelnorthlondon.blogspot.com

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