By the time this article is published, the armed assault on Afghanistan, the Taliban regime, Osama bin Laden or his followers may have already begun. For some, it seems, they are all the same. But not to speak out against this is either a serious mistake or guilty acquiescence of the bellicose plans proclaimed repeatedly by US leaders.

The west’s quiet acceptance, particularly among European countries, pains me. It should fill all of us with despair. Yes, there are big speeches and important agreements are signed. But ultimately, the west accepts – and even takes part in – the violent response.

That the US was going to react as it says it will should come as no surprise. But the submission of other nations was difficult to foresee. It is alarming that countries such as France and Spain have not raised their voices to say “no”: to reject the violent solution as the only available option; to uncover the big lie of a “final solution” against terrorism.

I live in a country that has been fighting terrorism for 30 years and that daily clamours for the rule of law as the best means to confront it. What is not possible is that Spain should now put on a military helmet and pledge unlimited support for the hypothetical bombardment of nothing; for the massacre of poverty; and for a breach of the most fundamental logic, which proves that violence begets violence. The spiral of terrorism is fed by the number of dead counted among its victims.

It has been said of terrorism, particularly the Islamic or fundamentalist kind, that it is a widespread threat. But it is a phenomenon that has been helped by the west’s rejection of all that is different from its own culture or “civilised religion”.

The west and its political, military, social and economic hierarchies have been more preoccupied with the abusive and shameful march of production, speculation and profit than with an adequate redistribution of wealth. It has favoured a policy of social exclusion over integration and progressive immigration. And it has insisted on maintaining – and insisted on payment of – external debt instead of using those funds in the same countries it is now asking for help and understanding. For all those conscious mistakes, the west is suffering the terrible consequences of fanatical religious violence.

Lasting peace and freedom can be achieved only with legality, justice, respect for diversity, defence of human rights and measured and fair responses. It is impossible to build peace on foundations of misery. Above all, it should not be forgotten that there will come a time when justice is demanded of those responsible for these mistakes and the loss of a historic opportunity to make the world more just.

I am not thinking here about the justice demanded of those who masterminded and carried out the tragic events of September 11. That is the remit of national or international justice, as well as the intelligence and police services that have to compile the evidence. This is necessary if a fair trial is to take place. It is not sufficient to say: “I have the evidence but I cannot make it public for fear of endangering my sources.” That is not a serious approach – it is simply illegal.

Of course, everyone has already established the guilt of Osama bin Laden and, as the indisputable leader of Islamic fundamentalist terrorism, he probably is guilty. We should not forget that we are dealing with a horrible crime – but the response nevertheless requires due process. In its haste to eliminate Mr bin Laden, the west seems to have forgotten this fact. And that is serious.

The justice I am talking about is that which should be brought to bear not only on the Taliban for its brutal and oppressive regime but also on the leaders of western countries, who, irresponsibly and through the media, have generated panic among the Afghan people. Faced with the prospect of imminent invasion, this panic has forced them to flee towards supposed security and freedom. In reality, however, it merely drives them towards what is certain to be a human catastrophe. Who will answer for these deaths? Who will answer for the forced migrations? In all probability, the death of a few thousand Afghans will be of no interest to these leaders because, for all the grand speeches, their fate is already sealed.

The response that I seek is not military. It is one based on law, through the immediate approval of an international convention on terrorism. Such a convention should, among other things, include: rules governing co-operation between police and the judiciary; rules that enable investigations to take place in tax havens; the urgent ratification of the statute of the International Criminal Tribunal; and the definition of terrorism as a crime against humanity.

The time has come to look at the principles of territorial sovereignty, human rights, security, co-operation and universal criminal justice through the same lens. That, and that alone, should be the aim of the coalition of countries against terrorism.

*Baltasar Garzon is Spain’s leading anti-terrorist judge. A version of this article first appeared in El Pais.