“FORTUNATELY, Eta is weaker than ever and I have no doubt about its final defeat. I say this quite serenely.”

Those were the words of José María Aznar, the Spanish Prime Minister, just ten days ago in a valedictory interview with this newspaper.

They are words that may return to haunt him, as similar declarations on the Basque terrorist group have returned to haunt his predecessors.

Señor Aznar is a famously imperturbable man, so much so that he walked calmly to hospital after Eta blew up his car with a bomb in 1995, but his serenity must have been shattered by the massacre in Madrid yesterday — because of its appalling human cost, of course, but also because of the potential damage to his reputation. This is true regardless of whether the bombings were the work of Eta or an Islamic group or, indeed, the worst nightmare of all, the two working together.

There is no doubt that Señor Aznar considered the apparent success of his anti-terrorist policy to be a highlight of his eight years in office.

He had more reason than anyone before him to believe that he had Eta against the ropes. Socialist Party (PSOE) administrations in the 1980s had embarked on a disastrous “dirty war” strategy against Eta, whose repercussions arguably gave the terrorists a broad enough Basque sea to swim in for many more years. When Señor Aznar’s Popular Party ousted the PSOE in 1996, he began to implement a policy characterised as using “only the law, but all of the law” against Eta. He would crack down hard, but he would not abuse human rights. With some exceptions, he seems to have honoured this policy, despite the appalling pressure of Eta’s repeated assassinations of his party’s local councillors.

Under his second administration, enjoying an absolute majority, he decided to go further and change the law, banning Batasuna, Eta’s political front, and a number of satellite groups. Contrary to many expectations, the Basque country did not explode in flames as a result. With the help of collaboration from France, his police moved relentlessly against the terrorists, dismantling one cell after another, foiling many attacks and capturing a number of significant leaders.

After the September 11 attacks in 2001, Señor Aznar seized on the popularity of the war on terrorism to convince the European Union and the United States to back his radical judicial offensive against Eta. The price was his high-profile support for the invasion of Iraq, which just might provide a clue to the motives of the bombers behind the outrage yesterday.

In the short term, however, Señor Aznar’s policy seemed to be extraordinarily successful in his final 12 months in office, when Eta killed fewer people (three) than in any year the group has been active since 1973.

And then, yesterday, it all seemed to fall apart. The bombs in Madrid claimed twice as many victims in one morning as Eta had ever claimed in an entire year and nine times as many as the group had killed in any single atrocity.

That, however, begs the question that no senior Spanish politician seemed to want to consider as the shock of the bombings sank in. Why would Eta have carried out an attack such as yesterday’s, where the modus operandi was different from its own? What if it were not Eta, but some other group, such as al-Qaeda, whose strategy has always embraced mass carnage? There are, of course, a number of reasons for believing that Eta carried out the attacks. First, most bombings in Madrid over the past 30 years have been its handiwork. Secondly, it traditionally carries out attacks during election campaigns. Thirdly, the police had intercepted an Eta unit driving a car bomb to Madrid only ten days previously.

The case against the bombs coming from Eta is, however, at least equally strong. Eta has traditionally made a pretence of trying to avoid civilian casualties and usually telephones warnings in advance, although these have frequently been brutally inadequate. The people who carried out the attacks were clearly bent on killing as many civilians as possible. There were no warnings and the bombs were placed on packed trains that could not possibly have been cleared, even if an alert had been sounded.

Another question is raised by the infrastructure required to place and detonate so many bombs almost simultaneously. The same Spanish Interior Ministry that told us yesterday that it was certain that Eta had planted the bombs has been telling us for months that Eta’s infrastructure has been weakened to the point of collapse. Some unknown group, operating like al-Qaeda before September 11, would have been much more likely to be able to carry out such a complex operation under the noses of the police.

The most important issue, however, is that of motive. Eta has carried out deeply unpopular attacks before, but nothing on this scale. Its political support has already been halved by its ending of its 1998-99 ceasefire. Many Basques who still supported Eta now do so grudgingly and it is an open secret that many senior members of Batasuna have been arguing for a ceasefire. It is hard to imagine anything that could have done the group more damage in its own heartlands than the attack yesterday.

An Islamist group, however, has many motives for a massacre, and especially in Spain. Señor Aznar’s high profile in support of President Bush and Tony Blair in the lead into the Iraq war would make Spain and Spanish citizens a favoured target. Spain is known to have been a hive of Islamist groups, fuelled by immigrants from the Maghreb. A group fired by apocalyptic thinking does not have to consider human suffering or political consequences. That has never been Eta’s style.

There remains the grim possibility that Eta’s leadership, cornered and debilitated, decided to make its presence felt regardless of the cost, after so many humiliating “failures” in recent years. And it does seem that this leadership, isolated in exile and younger with every successful police swoop at the veterans, lacks the relative political maturity of previous generations.

The most disturbing possibility is that Eta’s new leadership might have entered into some alliance with an Islamic group, as the Baader Meinhof Group did with Palestinian groups in the 1970s.

In the inevitable confusion that comes after such an event, only one thing is clear: whether these attacks represent a new departure for Eta, or the worst Islamist attack in Western Europe, or both, the face of Spanish and European politics will be deeply and terribly marked by March 11, 2004.

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