I’m in shock. So is every MP. It feels like Jo Cox’s murder was only moments ago. Many of us cried to see her sister Kim Leadbeater courageously take the seat Jo once held and make her maiden speech in front of Jo’s commemorative shield last month.

Coming so soon after the untimely death of James Brokenshire, the stabbing of the unfailingly magnanimous and courteous Sir David Amess has left MPs of every party hue in tears. He was a character. There was always a twinkle in his eye. He seemed never to bear a grudge. And his campaigns for Southend were legendary.

In truth, everything is not right in our body politic. We pride ourselves on being a safe country. We’re not like America with its terrible murder rate, but two politicians have died simply doing their job in five years.

We MPs pride ourselves too on making ourselves available to our constituents. Anyone can turn up at our advice surgery, catch us in Morrisons, chat to us on the bus or the train, bend our ear in the rugby club or turn up in central lobby and ask to see us. It’s in the nature of our constituency system that many constituents don’t just know where our office is, they know where we live. That openness is absolutely central to our democracy and we must never surrender it.

But I’ve seen our political culture go terribly sour over 20 years. Social media act as a vortex of nastiness. Anonymity inflames intolerance. It’s true that we politicians sometimes pour too much bile into the cauldron of politics too. So we need to do some real soul-searching. Let’s think before we spit venom in each other’s face. And please, please, please, let’s end the anonymity on social media that somehow seems to grant people permission to write things online they would never dream of putting their name to or saying to another person’s face.

But as I have been saying for many years, we also have to get serious about MPs’ security away from the parliamentary estate. That starts with the police. My local police have always been great in dealing with threats of violence to me. But I know from colleagues that this is patchy. One office manager was laughed at only yesterday by his police inspector when he asked what support was available. Others dismiss concerns as trivial or pay mere lip service to MPs’ security. That has to end. There needs to be a central set of standards governing all security concerns and much tighter coordination between police forces.

We MPs need to take our own security more seriously too. Mostly we shy away from insisting on security measures. We don’t want special treatment. We know the pressures on the police. We let our guard down. But any other workforce that had seen two killings in five years would rightly demand action.

So there must be a review of all MPs’ security arrangements, both in Westminster and in the constituency. We may have to insist on surgeries by appointment only. Sensible measures maintained and regularly reviewed can protect that pearl of great price – democratically elected representatives that are easily but safely accessible. We don’t want to live in fortresses. But I don’t want to lose another colleague to a violent death.

Chris Bryant is the Labour MP for Rhondda and has campaigned about the safety of MPs.