I never thought I’d hear myself say that Donald Trump is right.

But on one issue at least I’m in agreement with the US President: his call to America’s European allies to take back 800 Islamic State (IS) fighters captured in Syria makes sound sense.

Before I explain the reasons why, let’s just for a moment take stock of the current situation on the ground in eastern Syria.

As I write, the Kurdish-led Syrian Democratic Forces (SDF) backed by the US military are poised to capture IS’s last, tiny enclave, bringing its selfdeclared caliphate to an end.

By any standards the fall of Baghouz is a significant moment.

It ends IS’s grand project launched from the great medieval mosque of Mosul in northern Iraq in 2014, when Abu Bakr al-Baghdadi seized advantage of regional chaos to proclaim himself caliph, suzerain over all Muslim people and land.

In the years that followed, he and his cadres would go on to set up a barbarous governing system – with courts, a currency and flag – which, at its height, stretched from north-west Syria almost to Baghdad, encompassing some two million inhabitants.

It was a reign of terror the hallmarks of which were massacres, sexual slavery and the beheading of hostages.

Ever since 2015, however, a forceful international military response has pushed IS’s caliphate steadily back to the point where only a few hundred of its fighters now remain in the enclave of Baghouz on the Euphrates.

The SDF has already confirmed that most of those remaining fighters are foreigners.

Those who do not die fighting will be taken prisoner, which brings me back to Mr Trump’s call for Europe to take back its nationals who became jihadist fighters.

Prone to exaggeration, Mr Trump might be over-egging it somewhat in suggesting that if Europe fails to do so there may be no alternative at some time in the future but to release them.

That is not going to happen. Short of a calamitous shift in the military dynamic on the ground whereby the Kurds find themselves preoccupied with, say, advancing Turkish forces and are hard pressed to concentrate on securing the IS prisoners, they will remain incarcerated.

Quite simply, it’s in no one’s interests – least of all Washington’s – to have hundreds of jihadi fighters back in circulation.

That said, there’s no doubt the Kurds are currently struggling to cope with the responsibility of holding perhaps 1,000 IS detainees, many of them foreign fighters from up to 50 countries.

“We can’t do it alone,” was how it was summed up recently by Abdulkarim Omar, a leader of the Kurdish-led foreign-relations commission, which is affiliated with the US-backed SDF.

“Everyone is running away from the responsibility,” he insisted.

Like others who have visited this part of eastern Syria, I can vouch for the fact that the Kurds’ fledgling administration lacks the resources and capacity to put on trial, or detain indefinitely, so many people.

The Kurds then are right when they say they should not be left to shoulder this burden. Aside from recognising this, there are very sound, pragmatic and strategic reasons why it would make sense for Europe to take back its fighters.

Mr Trump alluded to this last weekend when he said that the US doesn’t want to stand by and watch as IS fighters “permeate Europe, which is where they are expected to go.”

While not all those fighters being held in eastern Syria are of European origin, many are. The prospect of them at some point being able to move around freely again, perhaps making their way illegally to Europe or rejoining the global ranks of IS or a similar organisation, is worrying to say the least.

No doubt this was very much on the mind of the head of Britain’s Secret Intelligence Service (MI6), Alex Younger, when he warned IS’s threat is likely to “morph and spread” and that its threat is “definitely not done” while attending the Munich security conference over the last few days.

Mr Younger also cautioned about showing triumphalism at the demise of IS, something Mr Trump, of course, is already doing by declaring a “100 per cent victory”.

This is where Mr Trump is wrong and, indeed, his triumphalism flies in the face of a recent report by his own US Department of Defence that warns an “effective, clandestine IS organisation appears to be taking hold.”

In describing the future course of IS, counter-terrorism officials speak of an “atomised, clandestine network of cells with a decentralised chain of command.”

This is the reality faced on the ground so, while Mr Trump is wrong to talk of all-out “victory,” he’s right in voicing concerns over the potential capacity of IS fighters currently detained being recycled into the jihadi cause and ranks.

For this reason alone the British Government’s reluctance to take back UK nationals who have served with IS or supported their ranks in Syria and Iraq is incredibly short sighted.

Evidently, it’s at odds too with the kind of thinking expressed by Britain’s head of overseas intelligence.

As its stands, the options are simple. Either run the risk of leaving those UK nationals in Syria and them rejoining IS as it goes back to its roots and re-galvanises itself as an insurgency – or bring them back.

In so doing they would effectively be taken out of circulation and an opportunity to glean invaluable intelligence gained. Adding to these considerations too is recognising the importance of having those accused of atrocities stand trial and, if convicted, facing punishment.

Time and again IS has shown its capacity for strategic retreats in hard times only to rebound when circumstances change.

As the MI6 chief made clear a few days ago: “The military defeat of the caliphate does not represent the end of the terrorist threat that we face”.

It’s time the UK Government woke up and recognised the long-term implications of any decision it makes not to bring back its nationals who fought for the jihadists.

It’s time it listened to Mr Trump on that point at least, even if it should ignore his boast of “victory” over IS.