The attack on Afghanistan and the continuing occupation are often been held up as necessary and legal. Obama has asserted that this war, as opposed to Iraq, is the ‘good war’. Alongside a range of other justifications, many defenders of the war constantly refer to supposed UN permission for the bombing, invasion and occupation.

It is my assertion that there is no mandate in international law for the attack and occupation. Further, I am in the fortunate position to have tested this idea of legality to some degree in a British military court and to have found it weak.

Why are we in Afghanistan? A question which seems trouble the 72% of the population of this country who want their service personnel brought home. One common response amongst the pro-war class is to proclaim that the British people do not understand reasons for the war and to then use one of the tired justifications such as security here requiring security there or Afghanistan potentially becoming an incubator for terrorism again and many more, virtually all of which are have been refuted. Personally, I think that’s an insult to the British people.

A better question might be: Why did we invade Afghanistan initially? Because to understand the present moment and the pending rout in Afghanistan, we might do well to understand how we arrived at this juncture.

Afghanistan was originally invaded because the Taliban, one-time favourite sons in the region, had refused to hand over a suspect in the 9/11 attacks without  evidence. The introduction of Al Qaeda as a hook to hang the coat of intervention on came later.

The US demanded Bin Laden and when the Taliban asked for evidence, a norm in international law pertaining to extradition, none was provided. Now it could well be that the Taliban lacked the capacity, political will or intention. They may not have known where Bin Laden was, for example. In terms of legality this is irrelevant, extradition requires evidence or charges.

It emerged some months later after what US academic Noam Chomsky has described as ‘the most intense international investigation in history’ that the understandable reason no evidence was produced was because none existed.

The FBI declared that although they believed the WTC/Pentagon attacks may have been planned in Afghanistan, they were implemented in Germany and the United Arab Emirates, and as we know none of the 9/11 bombers were Afghans. On the basis of this un-evidenced assumption, the bombing began three weeks later

These facts alone render the attacks illegal, but there is more.

One Admiral Boyce RN, acting as spokesman for the UK military, effectively announced to the Afghan people that they would be bombed until such time as they overthrew the Taliban.

By way of comparison, this statement is remarkably similar to those made by Colonel Gaddafi with regards to making the streets of an insurgent Benghazi run with blood, sentiments which created an entirely appropriate outcry. This was also a statement of aggression.

The UN resolutions on the subject reaffirmed earlier resolutions, called for international co-operation in counter terrorism, intelligence sharing and so on. But none of them, not a single one, called for or allowed the invasion of Afghanistan. In fact the resolutions did not even mention Afghanistan.

There is a fundamental reason behind the lack of a call for intervention, and this is because the UN literally cannot give permission for the invasion and occupation of a country. That is not its role. Its charter simply does not extend to anything beyond calling for measures within international law to be enforced and demanding that any warring parties end hostilities and engage in dialogue immediately. This is not to say vaguely worded resolutions are not re-interpreted to mean a nod in the direction of war, but that the UN was not meant to be the final tick-box for imperialist agendas.

In fact, according to international law, nations can only use force to defend themselves until other means are found to resolve the conflict and this was clearly not the case with the US and Afghanistan – the US was not under attack, nor were any of her allies and Afghanistan was not an aggressor; It was, however, one of the poorest and least developed countries in the world and one on the edge of famine at the time.

My own challenge to the legality of the conflict was thrown down in the build-up to my trial for refusing to deploy. The charge was desertion and my argument was that due to the manifest illegality of the war into which I and my colleagues were expected to deploy, per chance to die, I was not obliged to go.

My excellent legal team put this argument in the form of a carefully researched defence document. At the time the military were promising me many years in prison for my refusal and for speaking out publicly. We served the document arguing that the war was illegal in its conception and its conduct and we served it to the Ministry of Defence.

A week later my lawyers contacted them for a response and all the charges for desertion and disobeying orders were dropped as if by divine intervention. It seemed that when the forum as a court of law, the military and the government were less keen to repeat their creaking arguments then they were on BBC Newsnight.

All that remained was a rather piffling AWOL charge which I’d never denied. We had won the fight before we even got to trial.

My position had been confirmed; I was under no obligation to deploy to Afghanistan because the war there has just as weak a legal mandate as it does an ethical one.