Why is it that when Ukrainians speak to their close relatives in Russia and tell them that they are being bombarded by Russian shells and missiles, they’re not believed?

Indeed they are usually told that either it’s just not true or that it’s Ukrainian forces shelling their own people in an attempt to make Russia look bad.

The reason is that ordinary Russian people are now swimming in a sea of disinformation and alternative realities that have been created by President Putin.

So how has he achieved this?

First, over the years Russian journalists have been subjected to more and more restrictions, to the extent that, even before the invasion of Ukraine, the number of independent news organisations able to operate within Russia was alarmingly small.

Once the invasion began it became an offence, punishable by up to 15 years in prison, to deviate in any way from the Kremlin’s line on the war. This had two effects, first it led to the closure of all those media that refused to play along with Putin’s narrative and second, it meant that the remaining Russian news media only reported what the Kremlin wanted them to report.

But there’s another, perhaps even more sinister reason, why the media campaign has been so successful in indoctrinating Russians – and it is not entirely irrelevant to what has been happening both here and the United States.

Russians have been subjected to a barrage of relentless anti-Ukrainian propaganda dating back, not just to the invasion on the 24th February, but back to 2014 when Russian-backed separatists in the provinces of Donetsk and Luhansk broke away from Ukraine.

The Russian people were told then, and have continued to be told, that Ukraine is a Nazi state, that it is being used by NATO to threaten Russia and that, anyway, Ukraine was never really an independent country – it was always part of Russia or the Soviet Union.

As to understanding why this has been so readily believed we need to listen to the academic researchers who have been investigating disinformation, and why it can be so successful in convincing people that black is white and anything different is ‘fake news’.

The world is a complex place so to help us understand it better our mind organises it into a series of ‘mind maps’ – maps that help us navigate our way through the complexities of our own lives and also through all the news and information we read and see about the wider world. On a simple level if, for example, there is fog forecast, and a look outside confirms this, then it’s a fair assumption that our journey to work might take longer.

Any information that appears to conflict with this ‘map’ e.g. that the fog will make the journey quicker, will be rejected, even if evidence is presented that appears to back this up. We reject it because if we accepted it our brain would have to cope with ‘cognitive dissonance’ – the discomfort brought about by trying to accept information that runs counter to everything we believe in or have been told is true.

That’s why it is easier for Russian families to believe what they are told day-by-day, hour-by-hour, by their own media, rather than accept what their Ukrainian relatives are telling them. Adjusting to a completely new reality would be too challenging, hence it’s easier just to reject it as false information and fall back on information that confirms what we have always believed – it’s called ‘confirmation bias’.

Russia is an extreme case but one can see in Donald Trump‘s campaign to try and convince the American people that he won the 2020 election there are worrying parallels, and even the claim made by the Leave campaigners that we send the EU £350 million a week, is not a dissimilar tactic.

The only defence against such claims is robust and independent journalism. Even here in Britain, we need to be constantly on guard against attempts, particularly by governments, to limit media freedom. This week the UN’s World Press Freedom Day has been marked in many countries around the world but, one suspects, not in Russia. Boris Johnson is not President Putin, but disinformation is a virus that threatens us all.

Ivor Gaber is Professor of Political Journalism at the University of Sussex. He has worked in Ukraine training journalists and government officials in the theory and practice of independent journalism.