I'm a prison governor who has dealt with terrorists and I can tell you the government's plans will save lives

Terrorism and its consequences are not matters of academic abstraction – they paint the walls with the blood of men, women and children

Liberty and Amnesty joined a predicable chorus line of rights activists keen to criticise the government’s stringent new counter-terrorism proposals released this week. Now, as a former prison governor, I like an earnest do-gooder as much as the next man – as long as the next man isn’t a victim of violent extremism. Even a cursory glance at our profoundly broken sentencing and supervision system for terrorist offenders will tell you that we need to do much more to defeat this risk. Hand wringing is not good PPE.

The trouble is, no matter where you start on the dismal conveyor belt that leads from alienation to martyrdom, there’s an advocacy group or a well-heeled collection of progressives happy to shoot down any attempts the government makes to protect its citizens.

Take prevention as an example. Almost nobody argues against stopping the radicalisation of young people into hateful ideologies, animated by racism, sectarianism and extreme violence; of course that is better than picking up the pieces later on. But the left rarely has a good word to say about our own internationally-recognised strategy, known as Prevent, which is designed to do this sort of safeguarding. It’s constantly undermined as an oppressive charter to co-opt teachers and medics to become state spies, or criticised as inherently Islamophobic – despite the fact that referrals for assessment and treatment for those attracted towards the ideology of the far right are now in the majority through that scheme.

Further up this chain of misery, longer sentences for terrorists and the prospect of indefinite detention or supervision for those deemed to be a severe risk to the rest of us are regarded by rights charities as a fundamental attack on the pillars of British justice.

But these pillars delivered Sudesh Amman onto Streatham High Road. He had been automatically released from prison despite the fact that he was regarded as such a lethal risk. He was shadowed by armed surveillance officers, who were forced to shoot him dead when he started stabbing random citizens in the street. The public were rightly outraged by this failure to prevent a predictable terror attack.

The Streatham stabbing came hard on the heels of the murders of two young people by Usman Khan, released from jail on licence, who demonstrated the effectiveness of jail deradicalisation programmes by stabbing his advocates to death at London Bridge.

Outside the echo chambers of progressive social media, the man on the Clapham omnibus is horrified by a system that permits such atrocities to happen, seemingly powerless to stop it.

Should we just roll over and let the state have its punitive head? Not hardly. The Counter Terrorism Bill’s proposals should – and will – receive scrutiny in both houses of parliament. Figures including like the cross-bench peer, Lord Anderson, formerly the government’s independent reviewer of counter terrorism legislation, will turn their huge experience and intellect to this question, especially when it comes to ensuring that the executive can’t just bang people up indefinitely without good cause.

But the reflexive dismissal of the government’s response to it’s primary duty to keep citizen’s safe is predictable and depressing. The irony is that it is led by organisations that see themselves as deeply in touch with the “grass roots”. If that’s the case, the thoughts and feelings of Main Street UK are clearly stoney ground.

More time in prison for serious terrorist offences, as proposed, is absolutely essential if we are to have the time and space to understand the motivations of these individuals and counter their distorted thinking. Many of my European colleagues tell me that they are scrambling to put in place safeguards for their citizens because of very much shorter custodial sentences for serious extremist offences.

How we use that time is critical, however. Simply warehousing violent extremists for a few years longer without assertive and insistent efforts to deal with deformed identities will not render us safer in the long run. Incapacitating Irish terrorists in the 1980s and 1990s with no attempts to challenge the ideology that animated them resulted in better read, better prepared, more oppositional ideologues who developed their capacities so much they were able to participate in the largest prison break in British penal history.

Odd as it may seem, humanised regimes for terrorist offenders in custody offer us the best chance to listen to, understand and thwart future threats from them or their colleagues. If this can’t happen, then we can’t even be sure that reoffending won’t take place within the prison walls, let alone on release.

This isn’t simple and I’m not suggesting it’s easy. But the public see that. in the fraught calibration of the rights of the perpetrator and the rights of the victim, the government is firmly reacting to their needs. Terrorism and its consequences are not matters of academic abstraction – they paint the walls with the blood of men, women and children here and elsewhere. The danger that we destroy the liberties of all in pursuit of public protection from terrorism is a seductive notion and not one we should easily dismiss. But in the balance, we need protection for citizens more than liberal guilt.

Professor Ian Acheson is a former prison governor and led the 2016 independent government review into violent extremism in the prison and probation system