By Hamish de Bretton-Gordon OBE, former British Army officer and former commanding officer of the UK's Joint Chemical, Biological, Radiological and Nuclear Regiment and NATO's Rapid Reaction CBRN Battalion.
Most western and NATO countries have paid lip service to chemical, biological, radiological and nuclear (CBRN) defence since the end of the last Cold War.
It was perhaps lucky the Ministry of Defence did maintain some capacity to face the challenges to deal with the Novichok nerve agent attack in Salisbury in March 2018, where virtually all military capability deployed to support the police and emergency services for a quarter of an egg cup of nerve agent.
With a 100-year taboo on the use of chemical weapons and the red line well and truly broken, they are now normalised, and, due to their effectiveness and low cost, are likely to be the choice for most protagonists in the future.
The bottom line is that chemical weapons are morbidly effective for fighting in built-up areas, and the psychological terror they impart is exactly what terror groups look for in a weapon.
It is clear that the British Government now recognises CBRN as a major threat, and the standing up of 28 Engineer Regiment in a counter chemical, biological, radiological and nuclear (C-CBRN) role is the most tangible sign of this reinvestment.
We have learned, or perhaps relearned, four major lessons from both chemical attacks in Syria and Salisbury, centred on detection, decontamination, information and evidence collection.
All of the Union of Medical Care and Relief Organisations (UOSSM) hospitals I work with in Syria have good procedures in place and the equipment to survive chlorine barrel bomb attacks.
But they were completely caught off-guard when ISIS used mustard agent during an attack in August 2015 near Aleppo.
Once the substance was identified as mustard agent, the procedures and kit were both updated meaning we can now protect against chlorine, mustard and sarin.
But there is fear around the next development in the chemical weapons programme which is being operated in Syria.
The continued possible use of the nerve agent sarin in the country causes concern, but improved detection and training have dramatically reduced cross-contamination issues.
NATO detection capabilities were warning against Novichoks and are no doubt being addressed as a priority.
Basic detectors for every member of service personnel and first responders must be an aspiration – everyone can be a detector.
The lesson that keeps repeating itself since chemical weapons were first used is the need for decontamination.
Many people become casualties in chemical and biological attacks because they do not realise the nature of the attack and do not decontaminate properly, causing unintended secondary casualties.
At least 50% of UOSSM casualties in Syria have been from cross-contamination, with a similar figure found in the Novichok attack in Salisbury.
A lesson to be heeded as we potentially have to counter a wider outbreak of coronavirus.
CBRN is a difficult area from an information perspective.
It is often perceived to be specialist and difficult for the uninitiated to understand, and hence is an excellent hook for propaganda and misinformation.
Bombs and bullets are relatively easy for spokespersons to talk about and the public to understand.
The Salisbury attack has illustrated how difficult chemical weapons are in this respect.
The Russians, unworried by the truth or any collateral damage, waged an intensive, relentless and highly successful disinformation campaign.
Going forward, we must have guidelines for internal and external consumption, and they must be straightforward.
Government briefs in the wake of the coronavirus outbreak are clear and concise and suggest this aspect is now well understood.
In this era of fake news, where everything is questioned and used to distort reality, useable evidence is key.
The chance to collect evidence is often fleeting in the scenarios already discussed, and it is key military personnel and first responders have a basic understanding of how to collect evidence of chemical attack if they are in the vicinity.
Too often over the last eight years the Organisation for the Prohibition of Chemical Weapons (OPCW) have either been unable to get to sites of attack or have been delayed to an extent that evidence has disappeared or been tampered with.
A basic understanding of chain of evidence, collection methods and recording should become part of basic training requirements for those on the frontline.
Chemical weapons are firmly in the terrorist armoury, and the world is now aware of a highly advanced and toxic Russian chemical weapons programme and undeclared stockpile.
We could lose this battle through misinformation, before a gas canister has been released, if we are not agile and flexible with our internal and external messaging.
Most western militaries have paid lip service to chemical weapons defence since the Cold War; thankfully, this is now changing, but must gather pace, with better-informed risk management, to create and maintain operational tempo.
Most elite militaries like the UK's are now working on effective procedures to enable operations in the contaminated battle space and mitigate their terror.