This is a battle Vladimir Putin he cannot win, one who will ultimately – inevitably – put the sliders under his regime.
Every Russian has a mobile phone: Russians I know rely more on text-addictive apps than even we in the West.
Ukrainians call their friends and relatives in Russia. The same is true of Russians living in Europe, North America and Israel.
They send photos of captured Russian soldiers in tears, photos of children killed by Russian bombs, and the destruction of cities in Ukraine.
This means that Putin will not be able to suppress the truth about the war with Ukraine, despite his attempts to impose a totalitarian state.
About three million Russians have emigrated since Putin took office, and more are flooding now.
About 150,000 ordinary, decent Russians – including teachers, doctors and scientists – have chosen Britain.
The truth is directed to Russia through their phones.
In recent days, Putin has put pressure on the media to speed up the implementation of a law that could force anyone who tells the truth about the war to be jailed for up to 15 years.
His frustration and anger – and he really gets very angry – have reached a boiling point.
He plans to shut down parts of the Internet if he can, and ruthlessly limit social media. But Russia is not North Korea and would stop without cell phones.
Security forces detain protester during anti-war demonstration in St. Petersburg on Thursday
Russian President Vladimir Putin chairs a Security Council meeting via videoconference at the Novo-Ogaryovo residence near Moscow on Thursday
In addition – and this may come as a surprise to Britain – the Russians are used to freedom of speech. More than 100 million people in the country have no memories of adults living before the collapse of the Soviet Union in 1991.
Freedom of expression is alien to Putin, who was trained to oppose dissent when he was a KGB agent. After huge demonstrations against him in 2011, he initiated stricter repression.
For the past ten years, the infamous Foreign Agents Act has been used to suppress the media, NGOs, think tanks and individual dissidents.
During numerous visits to Moscow since serving as the British ambassador there, Russian friends in high-ranking positions decided to take me out into the open when they wanted to speak frankly.
But the restriction could not stop people from using their phones. Truck drivers used mobile phones to blockade Russian cities. Opposition leader Alexei Navalny (who is currently in prison) seriously hurt Putin with a YouTube video of his luxury palace, which garnered more than 100 million views.
More than 1.2 million Russians have signed an online petition against the war. Protests by a huge number of professionals are circulating on the Internet.
Many older Russians are still prisoners of Kremlin propaganda. They believe their army is there to eradicate the Nazis and fight NATO forces in Ukraine.
But the truth will spread through the moving vine. The Russians will see the brutality of this war. They were told to expect a quick victory. They will know that Putin lied.
The standard of living of ordinary Russians has deteriorated sharply due to the Kremlin’s corrupt mismanagement of the economy: life will now deteriorate greatly as a result of sanctions.
People sit at a bus stop while law enforcement officers line up during an anti-war protest against Russia’s invasion of Ukraine, in St. Petersburg
Russian opposition politician Alexei Navalny is pictured during his detention for an unsanctioned anti-corruption rally in Moscow in 2017.
Many of Putin’s top advisers know that he made a fatal misjudgment. They see how badly the so praised and expensive Russian army and air force have performed.
The only way out for Russia is to change the top, because Putin cannot back down.
His negotiators will have instructions on the merits to threaten the Ukrainians with destruction if they do not surrender. But for Ukrainians, as for us, sovereignty is non-negotiable.
Very few people in the Kremlin actually understand the way Ukraine has changed and developed over the last ten or 15 years.
There are two ways Putin can be forced to step down. One would be a mass uprising. I don’t think this will happen soon, because he will use maximum repression to stop him.
The other would be internal work by people close to him, who have come to the conclusion that this terrible mistake is costly for Russia.
It can take months to muster the courage. But once the truth about the war becomes widely known and the economy is shattered by sanctions and inflation, high-ranking officials will dare to look for another leader.
Their choice will probably be a strong man, almost certainly not a democratic liberal – someone who can get Russia out of Ukraine.
This is the beginning of the end of the Putin regime. Either through rebellion or through internal affairs, this unbalanced president will not survive this crisis for which he is fully responsible.
n Sir Roderick Line was the British Ambassador to Russia from 2000 to 2004.