ON shelves in my study sit a collection of books. Their titles are at one and same time both colourful, and malevolent. The Whores of War, Licensed to Kill, Congo Warriors, The Wonga Coup, and so the epithets adorning their front covers go on.

No less colourful and malevolent are the real-life characters who inhabit the pages of what I’ve come to call my ‘mercenary’ collection.

“Mad” Mike Hoare, Jean “Black Jack” Schramme, Costas Georgiou alias “Colonel Callan”, and Bob Denard, who revelled in the nickname les Affreux – the Dreadful – and whose life is said to have inspired Frederick Forsyth’s 1974 novel about mercenaries in Africa that was subsequently made into a fictional ­action movie – The Dogs of War.

Among my collection though there is one ­particular book entitled; No Mean Soldier.

It’s author, Peter McAleese, is a Scot who was brought up in Glasgow’s East end within the shadow of the “Riddrie Hilton” as Barlinnie Prison is sometimes wryly dubbed in the city.

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It was after service with the Parachute Regiment and SAS in Aden and Borneo, that McAleese joined the ranks of those global mercenaries whose lives have both fascinated and appalled me for decades during my time as a foreign correspondent. Hence my rather obsessive collection of memoirs and ­histories on the subject.

McAleese has spent most of his life in the school of hard knocks, from being on the violent, receiving end of a Glasgow hard man father who once broke his nose, to battling his way through murky civil wars in places like Angola.

But it was to be in the jungles of Colombia in 1989 that the final denouement in the story of this “soldier of fortune” came close to playing out.

It’s the events leading up to McAleese’s near-death moment in the humid rainforests of that troubled ­illegal cocaine-producing hotspot that form the ­incredible story of Killing Escobar, a new documentary that will have its world premiere today at the Glasgow Film Festival.

Shot in docudrama style with many of the actual events re-enacted by actors, it tells the picaresque and sometimes blundering tale of how McAleese is hired by the Colombian Cali drug cartel to muster and train a group of fellow mercenaries and undertake a mission to kill the infamous rival Medellin cartel drug baron, Pablo Escobar.

Given the film’s release, I thought it an ideal ­moment to ask McAleese about its making and his life. But more significantly perhaps, at a time when mercenaries have become a new and malign global force, to get some idea of what drives such dogs of war, both past and present?

For McAleese himself, there was he insists only one motive that drove him into the world of mercenarism.

“Most definitely adventure. Money is not the key motivator for me. In fact, most of the jobs I’ve taken had a very low salary and a lot of times you don’t even get paid,” he told me last week.“For me, it was about being part of something and the excitement of a new and bigger challenge ahead,” said the man who first joined the army aged 17 in 1960 and then later, on more than one occasion, found himself shuttling back and forth ­between the Parachute Regiment and SAS because of ­“disciplinary reasons.”

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The genesis of the film says McAleese came about when the film’s producers, the Glasgow-based Two Rivers Media and Salon Pictures, approached him about telling the story of what back at the time had been dubbed Operation Phoenix.

Many then believed the planned mission, first drawn up by a friend of McAleese, David Tomkins, a former safe cracker from Basingstoke turned mercenary in Africa, was not so much a daring mission but more a near suicidal attempt to kill who was then the seventh richest man in the world and one of the most feared drug lords and narco-terrorists. In the film McAleese describes the moment when he was first drawn into the plot.

“David came to me and said, ‘Are you interested in doing a job?’. I never asked what it was, I just said ‘yes’. Then he said, ‘Do you want to go to Colombia?’.”

Subsequently McAleese, and Tomkins were to liaise with Cali cartel security ­operative Jorge Salcedo, himself ­formerly of Colombian intelligence, to set the ­operation in motion.

Knowing the disdain many soldiers and former soldiers have for the movie and media world’s depiction of men ­under arms, I asked McAleese whether the resulting film was something he was happy with?

“They’ve done a good job in retelling the story as it was. I particularly like the section showing the training. You cannot see your own passion when you are there, you can only see how the men ­responded,” says McAleese of the 12 strong hired guns who joined his hit squad.

“We trained for 11 weeks solid. We trained so hard and had everything down to the fine detail like who takes my place when I get shot, what will the plan be if X, Y or Z happens,” he continued.

“The reality is not how Hollywood portrays it, it’s not easy. It takes a lot of preparation, grit and determination, and lots of very hard work,” McAleese says, confirming again the scepticism I’ve ­often encountered about film portrayals of military life and combat by those who have experienced it first-hand.

And speaking of scepticism, perhaps it would be no bad thing if some of those who make up the audiences watching the Hollywood style movie portrayals and “heroic” exploits of hired guns fully ­understood how far removed much of this is from the reality of a fraternity with more than a few egotists, psychopaths, and sadists in its ranks.

Costas Georgiou an ethnic Greek ­Cypriot, British mercenary alias ­“Colonel Callan”, who committed sadistic ­atrocities in Angola in the 1970’s and was subsequently tried and executed for his offences, is a case in point.

Along with Georgiou, others like ­British mercenary “Mad Mike” Hoare, Frenchman Bob Denard and Jean “Black Jack” Schramme, from Belgium, were among several prominent mercenaries to emerge in Africa in the 60s and 70s, who were elevated to near mythical status.

Movies like the 1978 epic The Wild Geese starring Richard Burton, whose character was said to be based on Hoare – who acted as technical adviser on the film – tend to characterise mercenaries as gentleman warriors or simple men on a mission who end up cynically betrayed by more powerful manipulative corporate or political forces.

Were the likes of Georgiou and Hoare typical of the mercenary breed, I put it to McAleese?

“I can’t say they were typical of the breed as everyone varies so widely in terms of their traits and character. Mike Hoare kept everything on a very tight rein. He treated it like he was running a battalion of the British Army,” replied the Scot.

“Costas (Georgiou) did not lack ­stomach, but his leadership skills couldn’t have been more different. With him it was leadership based on fear. If he didn’t like someone, he shot them. He was a very frightening character,” McAleese ­explained.

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IN Killing Escobar, in one of the many interviews used to narrate the story of Operation Phoenix, the Scot says he had no qualms at the idea of assassinating a gangster like Escobar.

This double-edged morality is common among mercenaries who use it to explain away their activities and actions in much the same way regular soldiers will talk in professional terms or say simply “it was ­either him or me”.

“For me, it’s not about killing, it’s about the mission, and what that achieves. ­Escobar had some good press locally ­because he’d done a lot for the area. But he couldn’t help murdering the ­opposition and anyone who stood in his way. That’s why I had no qualms about killing him,” says McAleese who was of course working for that very opposition, the Cali cartel.

In the film McAleese says that as a young soldier he was vehemently anti-communist and that communist ideology was perceived as the big threat in his day. In a very different world now what did he see as the biggest threats, organised crime like that undertaken by Escobar, or global terrorism?

“I think transnational terrorism is the biggest threat to world order ­today. What you have are people who are ­fanatics. They are prepared to give up their lives for their cause. They will do anything, and that level of commitment and ­determination makes it all the more ­dangerous,” he replied.

These days too of course ­mercenarism itself is a massive global business ­easily on the same scale as transnational ­organised crime. Military expertise for hire ranges from Russia’s Wagner Group ­operating in warzones like Libya and Syria, to South African mercenaries currently hired by the government of Mozambique to fight Islamist inspired terrorists, but who themselves have been accused of ­committing war crimes.

Those former soldiers who make up the ranks of mercenary groups also often flit between such work and that of ­“private security contractors” which have been used to outsource the work previously done by national armies. McAleese ­himself has worked in both mercenary and security contractor roles.

“I think that mercenaries and private security companies save ‘the powers that be’ having to send their own ­people. It means that countries don’t have to be seen to get involved. They don’t have to run the risk of being labelled as ­interfering. It saves the country from getting a bad name,” he explained, ­confirming the often ­“expendable” role with which ­governments view such fighters.

So, should international laws on ­mercenary activity be tightened up I put it to him?

“If you could tighten up international laws it would definitely help. There is the scope for them to be tightened, too. I believe that the powers that be don’t want it, though. It’s a hugely complicated picture as it depends on who is training and who is supplying. So, I’m not sure how achievable tighter laws would be,” McAleese admitted.

Despite this he doesn’t see modern day mercenarism as making the world a more dangerous place.

“Generally, no, I don’t believe it does. But in certain areas, it may do, for ­example Mozambique at the moment, which is really volatile. But it’s just ­pockets that are like this, not the whole world. Many companies operate without anyone knowing they are there. That’s when it works best,” he says, echoing back to his operation to kill Escobar.

It too was meant to be shrouded in ­secrecy at the time but in the end was ­subject to leaks that threatened the ­mission. Those familiar with the ­history of Escobar’s fate will probably already surmise what ultimately became of McAleese’s attempt to kill the drug ­baron.

Without spoiling the documentary for viewers, suffice to say the attempt to kill Escobar comes to an unexpected end that sees McAleese almost losing his own life while others involved in the mission are less lucky.

The 90-minute film using McAleese’s own words and never-before-seen archive footage makes for a compelling watch. But it might also make a discomfiting one for those who perhaps view mercenaries and their work as repugnant and morally reprehensible.

For those who take such a view it will matter little that the target, Escobar, was to many people the devil incarnate. A man who himself was a callous and ­brutal killer whose activities in Colombia and beyond were associated with an ­estimated 4000 murders. The drug lord and the dog of war, two wrongs don’t make a right, they may well contend.

AS for McAleese himself, he’s now long retired, his days of hoofing through jungles and jumping out of helicopters are long since over. How then does an old “dog of war” spend their retirement years?

“‘Dog of War’? I see myself as a ­normal guy who got myself into extremely ­difficult situations. I’m very content with my life now. I am involved in the Catholic Church, and appreciate my family more than ever, he tells me.

“I learned a very important lesson from my father, that I had to treat my children better than he treated me. So, I spend time doing that.”

Killing Escobar receives its world premiere at Glasgow Film Festival today. The film is being shown at virtual cinemas across the UK from March 12, tickets available from www.modernfilms.com/killingescobar.