The anger and anxiety caused by the Westminster attack is palpable but, as ever, Britain is doing its utmost to keep calm and carry on. This, along with the incredible actions and professionalism of our police and emergency services, inspires a strong sense of pride in my country and its people.

What constitutes a victory for a terrorist when they carry out an attack in a free country, aside from successfully killing and maiming innocent people, is to expose the vulnerability inherent in open societies and to compel us to violate the values that form an integral part of our culture. It is easy to give into such temptations and we have in the past but the best response to the actions of a fanatical killer is to never do the latter in a misguided attempt to address the former.

When one considers how easily this attack was carried out and how close the attackers got to our democratically elected representatives; it is impossible to deny that we are vulnerable. The murder of the police officer took place shockingly close to the yard where MPs enter the building, and where the car – which would later speed away with the Prime Minister – was parked. It was a chilling reminder of the terrifying possibilities of the blunt tactics of terrorism.

This atrocity combined the crude brutality of an improvised hit and run attack, mowing down innocent civilians, with the targeting of a hugely symbolic building and institution. Westminster is an icon of British democracy and Western Civilisation; the attack struck at the very heart of everything we stand for. Democracy, the rule of law, liberty and the settling of differences through peaceful politics and open forums. As the anger erupts in the wake of such an incident, we must remember and cherish the principles that underpin our society.

Our open, tolerant, liberal society is something to be proud of. Yes, they make us more vulnerable to terrorism, but we must carry on as we are and remember who we are.

Westminster is a public building and must remain open and accessible; we cannot cut it off. Our enemies must always be treated as our principles demand; within the rule of law. The demands to respond to barbarism with barbarism are misguided; that’s the attitude of the lynch mob, we are better than that. Calls to close our society by closing the borders and adopting a siege mentality must be ignored. Moves to further erode and abolish our liberties must be opposed. Otherwise, eventually there will be nothing left for us to defend and we will have lost.

The answer isn’t to renounce openness, tolerance and liberty; we must defend them to the hilt. The answer is not to become intolerant, it is to foster a strong sense of identity, belonging and inclusivity and to continue to try and make our societies prosperous for all. If we violate the values we purport to believe in then we prove ourselves to be unprincipled phoneys worthy of the contempt that the terrorist direct at us.

The most incredible photo of the harrowing scenes on Wednesday was one of the suspected attacker, who had been shot having stabbed a police officer, being treated by paramedics. What incredible professionalism, what an utterly astonishing sense of moral rightness; and what a fantastic symbol of the difference between civilisation and barbarism. The paramedics who were dutifully striving to save the suspect’s life represent perfectly what it means to stand by one’s principles.

It is difficult to comprehend for many people, as some of the vitriolic replies to my above tweet show. Many fully agreed with the sentiment, but many others – in their anger and resentment – repudiated it. Replies ranged from calling for him to beheaded, shot or hung to questions as to why they are bothering to try and save him. “Let him die!” they say. No!

They are trying to save his life because they represent the very best of Britain. They show that we are better than them. This is what it means to be civilised, this is what it is to be a free, liberal country. Cherish it and be proud.

The heroic paramedics were carrying out their duty to save lives no matter who the injured is, what they’ve done and what their race, religion or creed is. Their actions are an affront to the barbaric forces that seek to divide us and destroy our values. The very best outcome would be for the murderer’s life to be saved so they could face arrest and then, with proper legal representation, face an open and fair trial for their crimes; a victory for the rule of law.

This is not weakness; it is strength. It’s the exact reason our enemies will lose this ideological war. They are lowly murders, nothing more; just deluded losers who failed at life. This pathetic cowardly act was a petty little victory for “terror”. Sadly, their victory will be felt by the victims’ families for the rest of their lives and nothing can now change that.

If we stand up for what we believe in and unwaveringly hold to our values – just like those paramedics – we will win in the end. Our principles and the civilisation built upon them will endure, long after the dogma that inspired the attack has faded into nothing. The Palace of Westminster will still loom large, our people will live on, our democracy will stand tall; and everybody will have forgotten the name of the murderer.

Ben Kelly is an Executive Director of Conservatives for Liberty.