Leading article: An arrest that serves as a warning to other tyrants

IT WOULD be reassuring to think that every dictator, as he straightens his epaulettes in the mirror in the morning, shivers at the prospect of ending their days in prison -- and resolves to issue one fewer execution order. It is a fanciful dream, of course, but the arrest of Augusto Pinochet cannot be anything but good news: less for the sake of achieving justice for the families of the Chilean dictator's victims - it is too late for that - than for the sake of restraining totalitarian excesses in the future.

There is a happy air of bumbling British amateurism about the sequence of events which led to Pinochet's detention. Where the French government, under pressure from human rights activists, refused him a visa, the Foreign Office said Chileans did not need a visa to enter Britain. If this had been with the intention of springing the trap once the general was tucked under the covers of his private hospital bed, there would have been an admirable ruthlessness about the decision. But it would have been duplicitous. In a way, it is better that he should have been admitted to our open and tolerant country - and only then subjected to the due processes of international law when Baltasar Garzon, the Spanish judge, applied for his arrest.

It says something for the state of the liberal conscience in Britain that it takes a Spanish judge with a well-developed sense of right and wrong to get Pinochet under lock and key. The Independent reported that the former dictator was in a London clinic a week ago but, after reporting Amnesty International's plea to the Government to arrest him, we failed to demand that, under British jurisdiction, he should be brought to justice.

What neither he nor we reckoned with was the fact that the Government is now run by people for whom the 82-year-old general was a hate-figure in their formative political years. Peter Mandelson, Secretary of State for Trade and Industry, yesterday described him as "a brutal dictator" and said the idea of diplomatic immunity was "gut-wrenching". Jack Straw, Robin Cook and Tony Blair must have approved his arrest: when they were young and left-wing, the Chilean dictatorship was the symbol of all things evil. In a plot as satisfyingly rich as any of those of Marquez or Conrad, Pinochet was lured into a trap constructed by his own arrogance, his assumption of British friendliness based on the opposite ideological prejudice of the Conservatives, especially that of Margaret Thatcher.

You do not have to buy into the entire left-wing demonology to welcome an old tyrant having his collar felt in his twilight years - especially for the deterrent effect it might have on others. So far, the International Court of Justice at The Hague has been rounding up relative small fry in its trials of war crimes in the former Yugoslavia, but at least its shadow hangs over the Balkans, and by its action last Friday the British Government has at least demonstrated a political will to enforce international legal obligations.

What is more, all but seven countries in the world agreed earlier this year to set up a new court alongside the ICJ to strengthen the enforcement of international laws against genocide, war crimes and crimes against humanity. It would be utopian to suggest that such a body (especially until it is backed by the United States) would have averted any of our modern atrocities. So far, Slobodan Milosevic has been disappointingly unrestrained by any sense that he might end his days in a Dutch cell. But the new International Criminal Court - and the arrest of General Pinochet - gives new hope that dictators the world over might have to cast an eye over their shoulder as they imagine the weight on it of the long arm of international law.