Thirty years ago last Sunday, on a quiet Basque side road, ETA claimed its first victim. He was a young Guardia Civil called Antonio Pardines. Only a few hours later the activist who had shot him, Txabi Etxebarrieta, was himself killed by a policeman. He became ETA's first martyr.
A bloody cycle of "action-repression-action", of which Extebarrieta was a passionate advocate, had been kick-started. It has claimed more than 800 lives, and is still haunting Spain today.
At the time, Franco's dictatorship was itself nearly 30 years old. Many democratic Spaniards, who had little sympathy with ETA's aspirations to an independent Basque Country, privately applauded the daring of its members. Few could have imagined that, 20 years after Spain became a democracy, Guardias Civiles would continue to be shot by, and to shoot, ETA members. Nobody would have believed that ETA would also be locked in a bitter struggle with "its own people" - the large majority of Basques who accept the extensive self-government which the region has won.
Early last Friday, a team of antiterrorist police blew up the armour-plated door of a flat in Guernica. The charge failed to fully clear the entrance. In the ensuing seconds of delay, one of the ETA members in the flat leapt out of bed, grabbed her gun and allegedly came out shooting, wounding a policemen before she herself was shot dead.
The police responsible are controlled by the Basque government, not by Madrid. They are mostly Basque nationalists themselves. The street where the flat stands is named after Picasso, whose best-known painting was a furious protest at the destruction of Guernica by Franco's German bombers in 1936. The flat is only a couple of hundred yards from the historic Basque parliament building with its sacred oak tree.
The woman who died in such a symbolic setting was Inaxi Zeberio, the third ETA member to be killed by the Basque police, and the fifth female member to die "on active service". The police say they found documents which show her unit was planning to kill 30 people, including 25 conservative politicians, still a favoured target despite the revulsion at councillor Miguel Angel Blanco's murder by ETA last July.
Combined with a Spanish police coup against ETA's financial support network a week earlier, Friday's raid was a severe blow to the terrorists. But Zeberio's death has prompted allegations that the Basque police are engaged in a war as dirty as that waged by the GAL. It is most unlikely that there is any substance to this charge, but this will not deter the 10 per cent of Basques who still support ETA.
An Irish flag hung alongside the Basque ikurinea in Zeberio's home village on Sunday. But, despite repeated references to "la via irlandesa", there is no sign of a serious ETA ceasefire. Without one, the cycle of violence started 30 years ago seems doomed to continue.