The Basque peace process clearly went into fast-forward mode last Saturday night, with ETA's statement to the BBC that, at least for this generation, the war here is over. It is not so clear, however, where the process is going. Sunday's elections to the Basque Parliament gave ETA's supporters a major boost, though the conservative and anti-nationalist Partido Popular got an even bigger peace dividend, becoming the second-largest party for the first time. No party won an overall majority, and forming a government which will advance the peace process will be a difficult task for the biggest group, the moderate Basque nationalists of the Basque Nationalist Party (PNV).

ETA, and Basque nationalists generally, constantly stress the inspiration they have taken from the events which led to the Belfast Agreement. Their opponents in the big Madrid-based parties, the Socialists and the Partido Popular, have tried to argue that there are no similarities between the conflicts in Ireland and the Basque Country. The differences are now probably more illuminating than the similarities.

The most significant contrast is the relative strength of nationalism in each situation. Nationalism is obviously a minority force within Northern Ireland, but in the Basque Country, as currently defined, the reverse is true. A second difference is the relationship between conservative and radical nationalism. The Hume/Adams talks brought the SDLP and Sinn Fein slowly and publicly into a shared strategy. Until a few weeks ago, however, the PNV and ETA's supporters in Herri Batasuna were at each other's throats, at least in public.

Since the mid-1990s, HB has explicitly adopted a strategy known as kale borroka - street struggle. This involved almost daily rioting and regular "sabotage", including the petrol-bombing of PNV social clubs and burning the cars of PNV members. Meanwhile, the Basque police force, on the orders of a PNV-dominated regional government, came close to operating a shoot-to-kill policy against ETA.

The final schism within Basque nationalism seemed to come with ETA's killing of a young Partido Popular local councillor, Miguel Angel Blanco, in July last year. The PNV joined with the PP, and all the other democratic forces in the Basque Country and Spain, in condemnation of this murder. Millions demonstrated against terrorism, and the isolation of ETA seemed complete.

Over the last year, Herri Batasuna saw its central committee jailed for collaboration with terrorism, and its daily newspaper closed. The response from its supporters was relatively small-scale. ETA continued to kill PP local councillors, regardless of public opinion.

There was widespread amazement, then, when all the Basque nationalist forces, including the PNV and HB, united in September to produce the declaration of Lizarra. This manifesto proclaimed the right of the Basques to decide their own future. Four days later, ETA announced an indefinite truce. Last Saturday, ETA announced that its members would not return to violence "in this generation", no matter how little political progress was made. In the following day's elections, Herri Batasuna (now operating under the name Euskal Herritarrok) won 60,000 more votes and three more seats than in 1994. If its leaders have not yet borrowed Gerry Adams's suit or Mitchel McLaughlin's tie, they are already speaking a language which is as at least as democratically potent as Sinn Fein's, and which relies rather less on an implicit threat of violence if things do not go their way.

The contrast in the time-scale and the speed of the two peace processes is remarkable. In Ireland, matters advanced, and still advance, mostly by millimetres. In the Basque Country, the world seems to have turned upside down almost overnight. What explanation can be offered for such a bewildering shift in the political climate, and what are the dangers that it could shift back as easily to stormy weather?

Any answers must be very speculative at this stage, but a few things seem clear enough.

Despite the viciousness of the confrontation between radical and conservative nationalism in recent years, it was essentially a family row and both sides had a strong interest in ending it. The Basque Nationalist Party has always been ambiguous as to whether it wanted full independence, but it does believe the Basques have the right to make their own choice in the matter without having to ask permission from Madrid.

Just as much to the point, the PNV sees the introduction of European Monetary Union as a great opportunity for a newly dynamic Basque economy. Meanwhile, ETA knew it was in a cul-de-sac, though it retained its commitment to Basque independence, and a rather vaguely defined socialism. The collapse of communism left it without a strong ideological reference apart from nationalism. The IRA ceasefire deprived it of a sense of having brothers in arms elsewhere in Europe.

Its infrastructure was badly damaged by police successes, and its supporters, though unwaveringly loyal, were exhausted and demoralised. It wanted an honourable way, from its point of view, to enter mainstream politics, and the PNV threw it a lifeline. A split in the nationalist movement can never be ruled out, but most observers do not believe that a "real ETA' is waiting.

A year's secret conversations between the two groups led to the declaration of Lizarra and the ETA ceasefire. The declaration holds out the possibility of renegotiating the relationship of the Basque Country to the Spanish state.

It is still far from clear whether the next Basque government will be formed from the nationalist majority which supports the declaration. So far, Euskal Herritarrok has said it will not enter government, though it would support a nationalist minority administration. The other alternatives are highly problematic alliances between the Basque Nationalist Party and either of two anti-nationalist formations - the Socialists or the Partido Popular.

Whatever agreement is reached, however, the Basque electorate will expect the new government to advance the peace process. Much now depends on how the Spanish parties respond to the challenge of a united, non-violent nationalist majority in the Basque Country. It will not be easy for the Madrid-based parties to concede a Basque right to self-determination.