Paul Thomas: Diplomacy means getting your hands dirty for national interests

According to the multitude of critics, the early release of Lockerbie bomber Abdelbaset al-Megrahi showed western democracy at its muddle-headed, hypocritical worst.

(The only person convicted of the 1988 bombing of Pan Am 103 in which 270 people died, Al-Megrahi was recently released on compassionate grounds - he's terminally ill - after serving eight years of a life sentence.)

There was, they said, the misguided sentimentality which persuaded the Scottish Government that an unrepentant mass murderer deserved compassion, and the crass disregard for the victims' families. There was the moral bankruptcy that persuaded the British Government that massive oil and gas deals with Libya were more important than justice being done and being seen to be done.

And there was the naiveté of both Governments in believing that a capricious dictator would abide by the unofficial agreement that al-Megrahi would not return to a hero's welcome.

Al-Megrahi has always proclaimed his innocence and many believe him, or at least believe that the prosecution failed by some margin to establish his guilt beyond reasonable doubt. The United Nations-appointed observer was severely critical of both the proceedings and the outcome, while a Scottish law professor who devised the trial's framework described the verdict as "totally inexplicable". In 2007 the Scottish Criminal Cases Review Board concluded that al-Megrahi "may have suffered a miscarriage of justice".

Unlike his uncritical admirers, I'm put off by celebrated journalist Robert Fisk's colossal self-regard and working premise that the West is invariably both stupid and reprehensible in its dealings with the Arab world, but his immersion in the Byzantine manoeuvrings of Middle Eastern politics is unrivalled.

Fisk makes a compelling case that the bombing of Pan Am 103 was carried out by Iran's Lebanese proxies in revenge for the shooting down of an Iranian civil airliner by the US guided missile cruiser Vincennes a few months earlier. The comparison is worth dwelling on.

Some 290 passengers were on board the Iran Air A300 which was in Iranian airspace and not exhibiting an attack profile. For three years the US denied that the Vincennes was in Iranian territorial waters.

Despite evidence of a gung-ho mindset and raging incompetence on the Vincennes bridge, the US has never admitted wrong-doing nor issued an apology - on his retirement the captain was presented with the Legion of Merit.

New Zealand had its al-Megrahi experience in the wake of the Rainbow Warrior bombing. After French secret service agents Alain Mafart and Dominique Prieur were sentenced to 10 years' imprisonment for manslaughter, the UN brokered a deal which saw them transferred to a French military facility on Hao atoll. Within two years and in breach of the agreement, they returned to Paris to - stop me if you've heard this before - a heroes' welcome. The Government was castigated for putting commercial and political considerations ahead of principle. No doubt some accused them of betraying the family of the sole victim, Portuguese photographer Fernando Pereira.

The feelings of victims' families are important, but not paramount - if they were, we'd still have capital punishment. In the case of Pan Am 103, the families were compensated to the tune of $3.85 billion, a gesture Libya later insisted was a step towards better relations with the West rather than an admission of guilt.

At what point do principles become expensive self-indulgences? Would the satisfaction gained from keeping Mafart and Prieur in jail for 10 years have outweighed the commercial and diplomatic damage France would undoubtedly have inflicted?

Would it have served Britain's interests to wreck deals reportedly worth $14 billion by insisting that al-Megrahi spend the last few wretched weeks of his life in a Scottish cell?

The refusal to compromise might enable you to feel good about yourself, as they say, in the short term, but the conduct of foreign relations is essentially about protecting and advancing the national interest. That can mean getting your hands dirty and dealing with people you'd rather have nothing to do with.

As Winston Churchill said of his attempts to forge an alliance with Josef Stalin following Germany's invasion of the Soviet Union in 1941: "If Hitler invaded hell, I would at least make a favourable reference to the Devil in the House of Commons."

A detached observer might think the furore over al-Megrahi is a case of not seeing the wood for the trees, since his body has become a cell from which there is no escape. They might also think that the highest-minded contributions to this maelstrom of moral outrage has come from those who argue compassion for the dying, whatever their crimes, can never be misplaced.