Rishi Sunak and Keir Starmer should stop their parties' poisonous personal attacks: Andrew Vine

But then it dawned that our county had witnessed one of the most appalling acts of political violence motivated by hatred in living memory. Against the backdrop of a bitterly-polarised campaign over Brexit, questions began to be asked about the way our national debates are conducted and the role – even culpability - politicians have in whipping up emotions that can get out of control.

The tragedy of Mrs Cox should once again be at the forefront of our minds, because an intensifying and potentially dangerous nastiness is poisoning politics, and we ought to be extremely worried about where it might lead.

Character assassination risks overtaking debate about policy as the preferred tactic for both our major parties, and that is grossly irresponsible at a moment when events in the Middle East are producing some disturbing consequences in Britain.

Witness the baying mob that laid siege to former defence minister Tobias Ellwood’s home on the south coast last week, prompting police to warn him and his family to stay away.

Only a couple of weeks earlier, justice minister Mike Freer announced he will stand down at the next election because of the number of threats made to him and his family.

He had even been targeted by the man who went on to murder Southend West MP Sir David Amess in 2021.

As if to confirm hatred is no respecter of party affiliations, days after Mr Freer talked of the menace stalking him, Labour deputy leader Angela Rayner said she no longer goes out socialising because of fears for her safety.

She is the highest-profile MP to reveal concerns, but they are shared by a legion of others, from all parties, who have police-linked panic alarms in their homes or guards at constituency surgeries.

Meanwhile, antisemitic hatred and abuse is at a 40-year high with Leeds – home to one of Britain’s largest Jewish communities – among the places worst affected.

And just across the Pennines, in Rochdale, Labour is in disarray having disowned its candidate in the by-election to be held in nine days’ time because of antisemitic remarks, quite possibly leaving the way open for the divisive figure of George Galloway – formerly MP for Bradford West - to once again return to Parliament after making the conflict between Israel and Hamas a central plank of his campaigning.

These are all ingredients of a toxic atmosphere around our politics that neither the Conservatives nor Labour are doing anything like enough to address.

The killings of Mrs Cox and Sir David are terrible reminders of where the viciousness surrounding much public protest and debate can end, but there is too little recognition of that.

Instead, the two main parties are gleefully engaged in abusing each other at a personal level, seemingly heedless of the dangers of the unstable or extreme taking it as a signal that physical attacks are the way to ensure political blows really find their mark.

The personal insults were apparent last week from both parties, with supposedly humorous Valentine’s messages splattered all over social media.

Labour jeered at the wealth of Rishi Sunak and his wife and the Conservatives portrayed Sir Keir Starmer contorting himself into impossible positions to perform U-turns.

Both foreshadowed what will undoubtedly become familiar campaign themes in the months ahead – Mr Sunak is out of touch with ordinary people because he is rich and Sir Keir can’t be trusted.

And all of it personal, kicking the man instead of challenging his policies, fuelling animosity in the echo-chambers of social media where those advocating violence find an audience who cheer and may even embolden them to move beyond being merely keyboard warriors.

The Government’s appetite for engaging in culture wars that can be seen as deriding people’s beliefs on social justice or even what constitutes personal identity is not helping as it can inflame an already febrile atmosphere and foster an us-and-them mentality.

The rhetoric needs to be dialled down and the personal attacks brought to an end.

Months probably remain before we enter a general election campaign proper.

The major parties should use them to clean up their acts and defuse the dangerous nastiness taking the place of civilised debate.