We are now in the middle of one of the most serious confrontations between the West and Russia in recent times with little chance of relations improving and the likelihood that it could become even worse.

The situation has been described by Sergei Lavrov, the Russian foreign minister, as being “worse than during the Cold War”. In the apocalyptic vision of Lieutenant General Evgeny Buzhinsky, formerly of the Soviet general staff, “a real war, worse than a Cold War” could be on the horizon. The two sides, between them, have expelled close to 300 of each other’s diplomats. There is talk of more severe punitive measures and channels of communication are being shut down.

The West’s robust reaction, it should be remembered, has been led by the British government’s assertion that Russia had been responsible for the first nerve agent attack in Europe since the Second World War. Some ministers, Boris Johnson chief among them, have suggested that culpability lies at the top, with Vladimir Putin.

With 29 countries taking concerted action to kick out Russians working under diplomatic cover, Theresa May has been congratulated for organising an impressive diplomatic coup. But now with scientists at Porton Down unable to say where the agent, novichok, was produced, and Mr Johnson’s contradictory statements, the government’s stance is being held up to scrutiny.

The inability of Porton Down to ascribe blame to Russia means that intelligence is now the key factor in the accusation against the Kremlin. And such overwhelming dependence on intelligence, most of it unknown to the public, has inevitably led to comparison with the fake intelligence which was used to justify the Iraq invasion.

It is also perhaps inevitable that Mr Johnson would be in the centre of the controversy. In an interview two weeks ago he had stated that Porton Down scientists were “absolutely categorical” that the novichok came from Russia: “I asked the guy myself, I said ‘are you sure?’ And he said ‘there’s no doubt’.”

But “the guy”, Gary Aitkenhead, the chief executive of the DSTL (Defence Science and Technology Laboratory) at Porton Down, was pretty clear that although the scientists had ascertained the agent was novichok, “we haven’t identified the precise source”.

The foreign secretary’s aides are insisting that he was misunderstood and his words have been taken out of context. But at the same time, the Russian embassy gleefully pointed out, the Foreign Office deleted a tweet from last month saying that Porton Down had established that the novichok used in the attack definitely came from Russia.

The official British government position in blaming Russia is based on, it says: “Our knowledge that within the past decade, Russia has investigated ways of delivering nerve agents probably for assassination and as part of the programme has produced and stockpiled small quantities of novichoks, Russia’s record of conducting state-sponsored assassinations and our assessment that Russia views former intelligence officers as targets.”

Taken in isolation, these words do not appear to provide a “smoking gun” that proves the Kremlin was definitely responsible for the attack on Sergei Skripal and his daughter Yulia.

But then there is secret intelligence about the matter, says the government, which cannot be disclosed. This may have come from agents inside the Russian security or political establishment. Or it may have come from intercepts of Russian communications. Revealing details of how this information was obtained would place the agents in danger and, or, reveal GCHQ technical capabilities to Moscow.

There is also secrecy around how Porton Down concluded that the substance used was novichok. The samples taken from Salisbury could have been put through scientific tests that would reveal its chemical or structure, which could be matched with whatever is known about novichok, which, by all accounts, is very little.

The surest way, however, would be for samples to be compared with another sample of the substance made in the same lab. That is the way, for example, it was ascertained that the Assad regime had used sarin in Syria. The official position in this case is that the UK does not have any samples of novichok. But could it be the case that a sample had been provided in the past by a defector: something which, again, cannot be publicly disclosed?

The problem with the secrecy is that as well as protecting sources it can be used to hide ineptitude and manipulation.

Skripal attack aftermath – in pictures Show all 15 1 /15 Skripal attack aftermath – in pictures Skripal attack aftermath – in pictures Scene of attack Members of the emergency services in hazard suits fix the tent over the bench where Sergei and Yulia Skripal were found unconscious on a park bench in Salisbury in March 2018. Getty Skripal attack aftermath – in pictures Victim - Sergei Skripal The retired Russian colonel and former double agent for MI6 was in a critical condition in hospital for more than two months after being exposed to novichok in Salisbury. He was given refuge in the UK after being jailed in Moscow for treason. Mr Skripal came to Britain as part of a high-profile “spy swap” in 2010 in which four men were exchanged for ten Russian "sleeper agents" in the US. In this image he is speaking to his lawyer from behind bars in Moscow in 2006. AP Skripal attack aftermath – in pictures Victim - Yulia Skripal Yulia Skripal was struck down by a novichok poison alongside her father Sergei. Facebook Skripal attack aftermath – in pictures Scene of attack A police officer stands guard outside a branch of the Italian chain restaurant Zizzi where the pair dined at before falling ill. It was boarded off whilst investigators worked on the building and later found traces of the chemical weapon within it. AFP/Getty Skripal attack aftermath – in pictures Scene of attack Large areas of central Salisbury were cordoned off by police following the discovery of the Skripals. Traces of nerve agent were also found in The Mill pub. PA Skripal attack aftermath – in pictures Victim - Nick Bailey Detective Sergeant Nick Bailey, rushed to the aid of the Russian ex-spy and his daughter who were targeted with a nerve agent. He was hospitalized after aiding them and didn't leave until three weeks after the attack. Wiltshire Police/Rex Skripal attack aftermath – in pictures Police investigation - Skripal’s home Police believe they were poisoned at home, and detectives found the highest concentration of novichok on the front door of Mr Skripal’s house. Getty Skripal attack aftermath – in pictures Theresa May visits scene of attack Britain's Prime Minister Theresa May spokes with Wiltshire Police's Chief Constable Kier Pritchard near where the Skripal's were found. Britain expelled 23 Russian diplomats over the nerve agent poisoning and suspended high-level contacts, including for the World Cup on March 14. Theresa May told parliament that Russia had failed to respond to her demand for an explanation on how a Soviet-designed chemical, Novichok, was used in Salisbury. AFP/Getty Skripal attack aftermath – in pictures Skripal days before attack Sergei Skripal days before he was exposed to Novichok, that has left him fighting for life. ITV News Skripal attack aftermath – in pictures Police investigation - military involvement British soldiers were deployed soon after the attack to help a counter-terrorism investigation into the nerve agent attack. One of the places they were asked to help out with was Skripal's home and it's surrounding. They were asked to remove a vehicle connected to the agent attack in Salisbury, from a residential street in Gillingham. AFP/Getty Skripal attack aftermath – in pictures Police investigation Personnel in protective coveralls and breathing equipment cover an ambulance with a tarpaulin at the Salisbury District Hospital. AFP/Getty Skripal attack aftermath – in pictures Police investigation The investigation extended to the grave of Sergei Skripal's son Alexander in London Road cemetery. Getty Skripal attack aftermath – in pictures Police investigation The Counter Terrorism Policing Network requested assistance from the military to remove a number of vehicles and objects from Salisbury. EPA Skripal attack aftermath – in pictures Home Secretary visits scene of attack Home Secretary Amber Rudd visited the scene of the nerve agent attack at the Maltings shopping centre on 9 March. Getty Skripal attack aftermath – in pictures Yulia Skripal speaks for the first time Yulia Skripal, speaking for the first time, said she felt lucky to have survived the nerve agent attack in Salisbury which left her fighting for life. Ms Skripal said her life had been “turned upside down” by the assassination attempt. But the Russian national added she hoped to return to her homeland one day, despite the Kremlin being blamed for the attack. Reuters

In the case of Iraq, Tony Blair’s Downing St “sexed up” what paltry intelligence there was for its false dossier on weapons of mass destruction. One of the main human intelligence (humint) sources on Iraq’s supposed WMD arsenal was a defector called Rafid Ahmed Alwan, codenamed “Curveball”, who turned out to be a fantasist. Despite warnings from MI6 and German intelligence about his veracity, material provided by Mr Alwan was presented as authentic by the US and UK governments.

There is no evidence that the intelligence provided by the British government on the Salisbury attack has been falsified. Hamish de Bretton-Gordon, the former commander of the UK’s Chemical, Biological, Radiological and Nuclear (CBRN) regiment has asked the government to release some of the intelligence which points to Russian responsibility.

Mr De Bretton Gordon says he has seen some of the material and finds it “compelling”. Russia, he wants to stress, is using the propaganda war, and this needed to be countered: “I implore the government to get on the front foot and get the full story out.”

“Unprecedented levels of intelligence,” were divulged, according to government officials, to other countries, and highly classified information, which is normally shared only between the “Five Eyes” countries – the UK, the US, Australia, New Zealand and Canada – was supplied to close allies with the national security adviser, Sir Mark Sedwill, taking it to the European Union and the North Atlantic Council. Other countries were given differing levels of intelligence.

More than two dozen countries were, it seems, convinced by what was given to them by London and acted against Russia. It is, however, also the case that some of these countries took the opportunity to hit back at Moscow for their own reasons.

Emmanuel Macron’s presidential campaign had been targeted by Russian hackers and propaganda outlets like Russia Today and Sputnik, with Vladimir Putin supposedly backing his admirer Marine Le Pen and Front National. Russian diplomats were thrown out of Paris. Across the Atlantic, the White House, under the circumstances, could not resist pressure from the security and intelligence agencies to take action against Russia, although Donald Trump – under investigation for his links to Moscow – took the less harsh of the expulsion options he was offered. The Baltic states and Ukraine, with their traditional antipathy to Russia, were only too happy to join in the retaliation. Of the UK’s close allies, only New Zealand failed to act. The government said it could not find any Russian spies to throw out.