Shabnam Nasimi is a Third Sector Consultant. She is the founder and Chairman of the Conservative Friends of Afghanistan.

On Sunday, Britain faced its second terrorist attack in a matter of months by a radical Islamist and as always we are thankful for the speedy intervention of the police and MI5. However, it will not always be possible to respond in such a way and so the long list of terrorism cases needs to be shortened.

For two years, I was a Prevent Coordinator at Lewisham Council, leading the Home Office Counter-Terrorism Prevent Strategy, and while at the heart of terrorism lies many characteristics of a violent crime, the main difference that sets it apart from other forms of crime is the ideology behind it.

Yes, the role of the police and security forces is to protect the public, but let’s be clear that they will only be able to control terrorist threats – not deal with the ideology or theology that underpins it.

It is now time to ask some serious questions on whether legislation against terrorist offences in the UK is fit for purpose and what needs to change?

Firstly, banning ideologically violent material that falls in the hands of terrorists like Sudesh Amman who, like many, was radicalised as a teenager.  Whilst the government’s Prevent strategy identified and safeguards many vulnerable individuals who are at risk of radicalisation but work to counter the ideology is weaker. The amount of disturbing and horrific extremist material online would shock member of the public, yet only a handful is prosecutable by the current terrorist and hate crime laws.

It is concerning that gaps in legislation have made it difficult to act against possessing and viewing this ghastly online material. A renewed effort should be pursued based on Counter Extremism Commission Sara Khan’s recommendation for a focus on “hateful extremism”. Many have expressed concerns over the victims’ inquests last year, re-iterated by the Chief Coroner that there was no offence in possessing terrorist and extremist material and recommended the introduction of a new law that would ban materials of the “most offensive and shocking character”, putting it on a par with indecent images of children.

Secondly, recently and over the next few years, many dangerous terrorists will return to the streets of Britain from prison. I strongly believe that when the police and security services put a terrorist in prison, it is crucial to keep them separate from other vulnerable inmates who can be at risk of radicalisation. We need better resourced and supported de-radicalisation programmes to be implemented, providing terrorists who come out of prison the rehabilitation they need to turn their lives around when they leave prison.

Thirdly, however, while we don’t want to be a country that metes out harsh sentences, for radical Islamists there is little alternative. The government has shown determination to introduce emergency legislation to remove automatic early release for terrorists and to carry out risk assessments, but this needs to target all forms of terrorist offences, including offenders who possess and disseminate terrorist material. As was shown in the Streatham incident, Amman was clearly indoctrinated by a violent extremist ideology, yet no offence exists to ensure that the government can monitor or charge violent extremists, even when no one was harmed. There is a very little difference between possessing terrorist documents and disseminating terrorist publications and turning that into violence.

Last December, 74 terrorist offenders had been released from prison early and in the coming months even more are set to be released. The government is now planning to change the law to stop this and if we were able to change the law to enable the retrial and conviction of the Stephen Lawrence murderers, can’t we take the same approach to deal with urgent national security threats?

Whilst Britain has an effective counter-terrorism machine of integrated police and MI5 teams – three terrorist incidents within the space of a few months is proof enough that we need longer sentences of terrorist offenders. The bottom line is that we urgently need to deal with the root causes of radicalisation by interventional providers who are adept at countering the Islamist ideology, a justice system that reforms willing offenders and controls those with rooted extremist ideology.