Puzzling out the geopolitics of the Ukraine crisis is not as straightforward as it might appear. Of course, Vladimir Putin has taken the law into his own hands in an especially brutal (but entirely characteristic) way, breaching international agreements and committing war crimes. The world must find a way of holding him to account.

The reason he gives for the invasion - to de-Nazify his neighbour – is, of course, ridiculous, though he has made it obligatory for Russians to accept this nonsense or face 15 years in jail (including schoolteachers, who are required to lie to their pupils). He doesn’t believe it himself.

The main reason is the obvious one: to protect what he regards as his country’s security. He sees that as something he is entitled to judge for himself, and not be forced to accept whatever the United States, NATO or the European Union decide (without even consulting him) about appropriate arrangements for the former countries of the Soviet Union.

Having a democratic neighbour with European leanings, such as Ukraine, which might allow the Americans to have a military base close his border to add to the 800 overseas bases they still had around the world, was a nightmare for Putin. He was not prepared to accept it – and he calculated that he now had the power to enforce his will.

One should never under-estimate Russia’s paranoia about being attacked. They have good historical reasons for their fear. A little-known episode in the early 1980s, which never reached the world’s press at the time but has since been validated by historians, illustrates this paranoia, It is set out in Ben Macintyre’s book about the senior KGB officer, Oleg Gordievsky, the superspy who worked closely with MI6 for many years.

When the head of the KGB, Yuri Andropov, succeeded Leonid Brezhnev as leader of the USSR in 1982, he was convinced that his country was losing the Cold War and that President Reagan would seize the chance for a nuclear attack to destroy his country. He set about making arrangements for a pre-emptive strike by Russia.

This was all the product of Andropov’s fevered imagination. He was a very sick man who died two years later. But America’s attitudes and actions in that period seemed to bear out his fears. Reagan talked toughly of “the evil empire” and moved Pershing 11 missiles into Germany with the power to strike at Moscow.

When Gordievsky passed on this information to MI6, they moved quickly, talking to both Margaret Thatcher and Ronald Reagan, urging them to lower their rhetoric. Both obeyed and extended a hand towards Russia to discuss arms agreements. Operation Ryan, as the Russians called it, was called off, but the episode has been described as the closest the two countries had come to nuclear war since the Cuban crisis two decades before.

I have written here before that the efforts of the US, NATO and the EU to stretch their influence as far east as possible since the collapse of the Soviet Union in 1991 ran the risk of awakening the anger of the Russian bear. Now it has happened and no one should really be surprised. To some extent, therefore, the west must bear its share of the blame for what exploded in Ukraine.

For the past three decades, ever since the end of the Cold War, the world has been dominated by the United States. When it was humiliated by the 9/11 terrorist assaults, it took revenge by invading Afghanistan in 2001. When Saddam Hussein appeared to be a threat to American influence in the Middle East, the US launched a war on Iraq two years later.

Neither of these wars were successful and reduced America’s standing around the world. They also resulted in the deaths of many times more innocent civilians than poor Ukraine has suffered.

When Putin saw the shambles of Joe Biden’s retreat from Kabul he identified a weak enemy and believed the time was right to challenge the US hegemony. Three things gave him the strength he had lacked before: the Russian economy had thrived on sales of oil and gas, building up a sizeable war chest; the war in Syria had given him confidence in the effectiveness of his military forces; and since 2013 he had had a willing partner in Xi’s China to challenge US power and the over-mighty dollar.

Xi will have been watching the Ukraine invasion with keen interest, because he could see it as a dress rehearsal for his own threatened seizure of Taiwan. If that is the case, he will have been shaken by Russia’s failure to secure a knock-out victory in Ukraine and by the hatred of Putin it has created around the world.

So far Putin appears to be winning his domestic propaganda war, though the death of Russian soldiers will count against him, especially if the bereaved families protest in greater numbers. His popularity will not be helped by the sharp fall caused by western sanctions on what are already abysmally low standards of living among the Russian people.

It is impossible to know if any of this will be enough to oust him from power; one can only hope and pray. For a man often plausibly described as mad, he has got himself into a powerful position where nobody, apart from the plucky Ukrainians themselves, can halt his invasion – not the American President, often described as the most powerful man in the world, nor the combined opposition of Europe and the United Nations.

As for sanctions, he holds the power to retaliate by cutting off energy supplies to the whole of Europe. His offer to withdraw from Ukraine if it becomes a neutral state is fiendishly clever, putting the US in a quandary if it refuses.

One can’t help thinking of that reported war chest of 634 billion dollars and what that amount of money could have achieved in developing Russian society and improving the education, housing and jobs of the people, rather than ploughing it into weapons to fulfill his grandiose dreams. That could have been a handsome legacy for Putin: instead, his memory will be reviled for injustice and bloodshed.

RIP Shane Warne

Shane Warne was so full of life and sharing his joy in living with others that reports of his death at the age of 52 were hard to believe. He was the best spin bowler of all time and a man who was bigger than his sport. One can only mourn the untimely death of someone who had so much to offer a gloomy world that needs his positive qualities more than ever.