No one can be sure that Eta's truce is not a trap. But if the example set earlier this year by IRA/Sinn Fein - with whom the Basque separatist movement is said to have had frequent and friendly contact - is anything to go by, the omens are more than promising.
The political violence which began in four European countries at more or less the same time, had two distinct wellsprings. Despite operational contacts and structural similarities, the nationalist terrorists in Ireland and Spain had vastly different goals from the left-wing groups in the former West Germany, and the far right, soon joined by the far left, in Italy.
For Basques and Irishmen, it was a matter of achieving their own country. The slaughter they wrought was far greater: 800 dead in the case of the Basques, some 3,000 in all in Ireland if republican and loyalist atrocities are combined. The nationalists' targets were across the board: local and national politicians, policemen, soldiers and innocent civilians.
But for the terrorists in Italy and Germany, and to a far lesser extent France, the mayhem was on a much smaller scale. Its driving force was perverted ideology, driven by frustration at ossified, unrepresentative and exclusive political systems, which, they reasoned, could only be brought down by political violence.
In the case of the far right in Italy, whose deadliest deeds were the 1969 Piazza Fontana bombing in Milan, and the Bologna train station massacre of 1980 - the deadliest single terrorist act in modern Italian history in which more than 80 people died - the theory was that random mass violence would create an irresistible clamour for the ultra-authoritarian regime they wanted.
The logic of the left took the madness a stage further. Their attacks were directed against individuals - usually bankers, generals, or politicians - as symbols of a despised system. These murders too aimed to provoke a crackdown. But repression would be followed by a mass popular uprising, out of which would emerge the leftist utopia.
In Italy the main groups were the Red Brigades and Prima Linea (Front Line), spiritual heirs of the 19th-century anarchists, whose most notorious deed was the abduction and murder in 1978 of Aldo Moro, the Christian Democrat leader, as he attempted to reach an "historic compromise" with the Communists.
Their West German equivalent was the the Baader Meinhof gang, out of which grew the Red Army Faction (RAF). Their victims included the banker Hans-Jurgen Ponto, and Hanns-Martin Schleyer, the industrialists' president.
But by the mid-1980s in Italy, and around 1990 in Germany, such terrorism was finished - through a combination of good police work, pentiti or "repentant" terrorists in Italy, and a realisation that violence only increased, rather than undermined, the legitimacy of the systems they sought to overthrow.
In Germany, although the RAF only formally dissolved itself earlier this year, the coup de grace was the disappearance of East Germany and the sanctuary it offered.
In Italy too the end of the Cold War allowed a more normal political system to emerge, rendering terrorism pointless.
Only some of these factors applied to the nationalist movements. But over 30 years they too have been worn down: by concessions granting them some of what they wanted, by the growing importance of political wings of their respective nationalist movements in Ireland and Spain, and a slowly dawning realisation that their wars were unwinnable.
Thus, if political momentum towards a settlement can be maintained, terrorism in both countries should logically be marginalised and ultimately disappear.
Terrorism of course tends to obey a logic of its own. But Euro-terrorism of the old variety seems on its death-bed.
What will remain is a cruder, less organised violence, mainly right wing, and racist and ultranationalist. It is hardly a threat to the system. But as ugly events in Germany, Italy, France and Britain show, it is not to be dismissed out of hand.
And, if the new terrorism locks horns with terrorism imported by the unwanted immigrants from outside Europe, it could get worse.
The ingredients of trouble abound. The Algerian population in France, so disliked by the far right, has links with the protagonists in the savage war in Algeria proper.
Kurds in Germany meanwhile could find themselves mobilising against Germans instead of Turks. The threat of economic downturn only increases the threat.Reuse content