THE CLOCK IS ticking. At the time of writing, the US military has just four days to evacuate approximately 12,000 soldiers and civilians from Kabul Airport.

Pentagon Spokesperson John Kirby confirmed today that of this number, 5,400 are Afghan civilians. These will be the last refugees to be airlifted from Afghanistan by the US before the Taliban’s deadline of 31 August.

The remaining 6,600 persons crammed into the airport consist of diplomatic staff and US troops. This is an extremely delicate moment for the United States military. Over the next 72 hours, US forces will conduct a retrograde operation – a tactical withdrawal by air – after 20 years of combat in Afghanistan. This withdrawal will be conducted in full view of the enemy – the Taliban – and the international media.

The military situation is critical. Hamid Karzai International Airport is completely surrounded by Taliban fighters. The Taliban have had almost two weeks to consolidate their absolute control of the area outside of the airport’s perimeter. They have also had ample time to dominate all of the high ground around the airport.

The Taliban possess multiple anti-aircraft weapon systems – from shoulder launched surface to air missiles to high powered anti aircraft guns. They also have high-calibre weapons that can be trained on the airport – from heavy mortars to field artillery pieces deployed in the direct-fire role.

As a consequence, the Taliban are in a position – at any moment – to target aircraft landing or departing the airport or to saturate the area with high explosives and shrapnel. Thus far, the US, British and other coalition forces have only been able to evacuate their personnel with the consent and cooperation of the Taliban.

Critical moment

This ceasefire is very tense. Yesterday’s suicide bomb attack at Abbey Gate – with the loss of 90 lives, including 13 US soldiers – was a dire reminder of the precarious position within which the US military find themselves.

Over the next 24 hours, the 16th Air Assault Brigade of the British armed forces will evacuate, leaving their US allies behind. Other nationalities have already departed. Armed groups such as Islamic State in Afghanistan (ISIS-K) will be watching this situation and planning to exploit it as best they can. ISIS-K have already claimed responsibility for yesterday’s suicide bomb attack.

Islamic State is estimated to have between 1,500 and 2000 fighters in Afghanistan. The Taliban have demonstrated that they are not capable of holding back these ‘jihadis’ from the perimeter of the airport. ISIS-K will be planning further terror attacks on the dwindling US forces as the Taliban deadline approaches.

Simply put, ISIS-K has a very narrow window of opportunity to attack and kill US troops before their hasty withdrawal. It is a race against time – on all sides – that resembles a ticking time bomb.

If Islamic State were to carry out further suicide bomb attacks at the perimeter, they will gain the international media coverage and notoriety that they crave – seeking more and more propaganda ‘victories’ against the retreating Americans. Worse still, if they can mortar the airport – targeting the densely crowded airport with high explosives – they could potentially inflict heavy casualties on civilians and military personnel alike.

They could also hit aircraft on the ground – full of highly explosive aviation fuel. The stakes are very high for all of those involved in the final days and hours of the US operation in Afghanistan.

Western forces

Once the British military have departed, US forces will begin their withdrawal in earnest. They will commence a tactical withdrawal – known as a collapsing perimeter. As US troops leave, their force protection element – manning the perimeter of the airport – will steadily deplete.

In this incremental process, the operational security of the ever decreasing numbers of US troops will deteriorate. Hence the term, ‘retrograde’ operation. This will represent an extremely dangerous moment for US forces. The last cohort of troops will be vulnerable to attack and will require a very strong top-cover or air support element from fighter jets to support their final departure.

Over the coming days – the last moments of Operation ‘Enduring Freedom’ – there will be significant pressure on groups such as ISIS-K to mount a ‘spectacular’ attack on departing US troops. They will seek to attack them on the ground by any means possible and attempt to take down a US aircraft.

In this regard, the remaining US troops will be particularly vulnerable. As the last aircraft take off – at low altitude in an unprotected civilian airfield, dominated on all sides by high buildings and hills – they will be particularly susceptible to direct fire weapons.

Military aircraft carry countermeasures against missile attacks – such as chaff to deter wire-guided missiles or flares to deflect heat-seeking missiles. Ironically, however, they do not carry countermeasures for the type of primitive direct fire weapons used by groups such as the Taliban and ISIS-K.

These line of sight weapons are normally out of range of heavily fortified airfields – with defences in-depth. But, this is Kabul – an open civilian airport surrounded by the enemy. This is a scenario that no military commander would choose. Particularly with an enemy whose hallmark is a propensity for a suicide attack.

The options for the US military in the coming 72 hours are stark. If they are incredibly lucky – and with the cooperation of the Taliban – they might get out of Afghanistan with little incident. If however, they come under partial or sustained attack, they will have to counter-attack and stage a fighting withdrawal.

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Uncertainty

That will inevitably lead to escalation with all parties to the conflict and massive loss of life. For President Biden and the United States, the most appalling scenario would be the capture and detention of US troops unable to extract from the airport before the Taliban deadline.

Trapped in the airport and robbed of the capacity to take the initiative by any other means, the US military may engage in deception planning in the coming days to accelerate and expedite their evacuation.

They might for example – as they did at Bagram Airport in July – disappear overnight, a day or so ahead of the expected deadline. Whatever happens in the next 72 hours, the stakes for all involved have never been higher.

Whatever the outcomes, it is certain that the images captured in the next few days will become iconic representations of the West’s latest failure to impose a military, diplomatic or political solution in central Asia.

It will also represent the beginning of a new and brutal chapter for Afghans under Taliban rule – particularly for the 18 million women and girls who remain there.

Dr Tom Clonan is a former Captain in the Irish armed forces. He is a security analyst and academic, lecturing in the School of Media in DIT. You can follow him on Twitter.