We must confront Russian propaganda – even when it comes from those we respect

Yes, there is something we can do. Something that, even if small, is meaningful. The propaganda war has always been crucial to Vladimir Putin. He uses floods of disinformation to confuse and misdirect people overseas and bolster support at home. The Kremlin knows that every action requires an apparatus of justification. Russia cannot continue its costly war without the consent of its troops and many other citizens.

Putin’s troll factories are notorious for turning out misleading claims, but their power is limited by their lack of credibility. What serves him well, as a study by Cardiff University’s crime and security research institute suggests, are “organic comments”: statements by real people, repeating and amplifying his propaganda. These are liked or upvoted by his bots then reproduced in Russian media to create the impression that he has widespread overseas support.

Obviously, real people have a right to express their opinions, however mistaken. But, given their utility to the Russian disinformation machine, I believe we have a duty to debunk and contest misleading justifications. In doing so we could, in our very small way, help the resistance in Ukraine.

This puts me in a difficult place. Among the worst disseminators of Kremlin propaganda in the UK are people with whom I have, in the past, shared platforms and made alliances. The grim truth is that, for years, a segment of the “anti-imperialist” left has been recycling and amplifying Putin’s falsehoods. This segment is by no means representative: many other leftists have staunchly and consistently denounced Russian imperialism, just as they rightly denounce the imperialism of the US and UK. But it is, I think, an important one.

At the end of last year, the writer and film-maker John Pilger claimed “it was the US that overthrew the elected govt in Ukraine in 2014, allowing Nato to march right up to Russia’s western border”. This is a standard Kremlin talking point, dismissing the revolution as a US coup. Ukraine, of course, is not a Nato member.

Outrageously, in my view, he maintains that on the day of the invasion, “Putin reportedly offered peace if Ukraine embraced neutrality and rejected Nato’s arms”. It is hard to see how Putin’s demand for surrender could be interpreted as a genuine peace offer. As Russian tanks rolled across the border, Pilger asked us to “imagine a strategic enclave of Britons, or French, or Germans, or Americans under violent siege – shelled and terrorised – for eight years”. This seemed to echo Putin’s speech the previous night: “The purpose of this operation is to protect people who, for eight years now, have been facing humiliation and genocide perpetrated by the Kyiv regime”. The BBC reports that Pilger’s claims have been widely shared by accounts spreading Russian propaganda.

I see the Stop the War coalition’s letter of 18 February, signed by many fine and eminent people, as strangely unbalanced. It stated that it “opposes any war over Ukraine”, but said nothing about Russian aggression. It appeared to blame only Nato and the British government, and urged “the entire anti-war movement to unite on the basis of challenging the British government’s aggressive posturing and direct its campaigning to that end above all”.

The coalition has recently produced a map showing Crimea, following its illegal annexation, as part of Russia. Its deputy president, Andrew Murray, has claimed it’s a myth that Ukraine wants peace. He has also reproduced a classic Kremlin falsehood: that in Ukraine, “Russian has been banned from the public sphere”. Fiona Edwards, a member of the coalition’s steering committee, has insisted that “Nato is the aggressor, not Russia”.

There is a strong argument that Nato should have been disbanded at the end of the cold war. But while Putin’s sense of threat seems to have been heightened by Nato expansion and mission creep, Nato expansion has also been driven in part by Putin’s belligerence. Are we really to believe that Estonia and Latvia joined because they wanted to attack Russia? On the contrary, it’s because they fear attack. While Nato’s growth is likely to have contributed to the crisis, it’s ridiculous to suggest that Russia is not the aggressor.

The former Labour MP Chris Williamson goes even further. As Putin’s tanks rolled across the border last Thursday, he characterised the government of Ukraine as a “post-coup, neo-Nazi backed, corrupt regime”, a classic Kremlin smear. The Morning Star, to give one of many similar examples, falsely describes Volodymyr Zelenskiy’s administration as a “fascist government”.

Harmful as this propaganda is, leftist support for another of Putin’s projects has even more serious implications. Since Russia threw its weight behind Bashar al-Assad’s regime in Syria in 2015, “anti-imperialists” in western nations have, unwittingly or not, helped to airbrush some of the world’s worst atrocities. Pilger, the late Robert Fisk and the celebrated journalist Seymour Hersh have all helped undermine well-attested reports of Assad’s use of chemical weapons.

As Peter Tatchell has explained in the Independent, the Stop the War coalition has taken a bizarrely one-sided approach to the conflict, focusing its anger on the US, though the great majority of atrocities have been perpetrated by the Assad government and its Russian backers. A group of professors at UK universities, who call themselves the Working Group on Syria, Propaganda and Media, has helped spread extremely dangerous, unsubstantiated claims about the White Helmets: a rescue force that pulls people out of the rubble after airstrikes in Syria. One member of the working group, a professor of genetics at Edinburgh University called Paul McKeigue, has suggested that the White Helmets might have staged “managed massacres”, perhaps involving captives “killed in some improvised gas chamber”, whose bodies they then spread on the ground. I see such conspiracy theories as a kind of leftwing QAnon.

McKeigue also revealed to an investigator posing as a Russian intelligence officer, with whom he thought he was collaborating, that he had been liaising with Russian embassy staff in both the UK and the Netherlands.

False information about Syria is also widely recirculated by Kremlin bots and used to justify Assad’s attacks. It is likely to have real-world impacts, as it reduces the political cost of the regime’s atrocities. Careless talk costs lives.

True anti-imperialism means opposing not only the west’s imperialism, essential as this is. It’s about opposing all imperialism, whether western, Russian, Chinese or other. It’s about opposing all aggressive wars, regardless of who wages them. It’s about resisting the temptation to believe that your enemy’s enemy must be your friend.

• George Monbiot is a Guardian columnist