A few weeks ago, ETA, Spain’s savage terrorist group, declared a “permanent ceasefire” and left 44 million Spaniards facing the dilemma other societies have faced: should one negotiate with terrorists?

ETA has killed more than 800 people in the last four decades in its quest for Basque independence, despite the fact that Spain’s post-Franco constitution gave it the largest amount of autonomy among the seventeen regions into which the country was divided.

Although a 1998 ceasefire was short-lived, this latest announcement—originally made by three masked figures with the usual theatrics—is more promising. The ETA, weakened by the police in recent years, has not killed anyone since 2003. Meanwhile, the Spanish government of Mr. Rodríguez Zapatero has already undertaken negotiations with Catalonia that indicate a willingness on the part of Madrid to expand the considerable autonomy enjoyed by Spanish regions.

Having lived under terrorism in Peru, Spain and Britain, and witnessed, as a foreign correspondent, the beginning of the peace process in Northern Ireland, I am familiar with the agonizing dilemma a society faces when challenged by terrorism. A negotiated solution imposes trade-offs that seem morally inexcusable. But given certain conditions a negotiated peace process is the best hope of actually obtaining peace. Even though I share the repugnance many of the victims of ETA and their political supporters are expressing at the thought of a negotiation, I think that country has entered a process that will result in the end of terrorism. There is no choice but to engage these cold-blooded murderers. Of course, the ultimate condition for any settlement should be decommissioning their weapons.

Whenever one tries to establish a parallel between Spain and Northern Ireland, skeptics point to the myriad differences that separate them, starting with the fact that one situation derives from a colonial condition. However, when comparing peace processes what is most relevant is not so much the origin of the grudge as the process itself, from the first signs that a deal is possible to the delivery of full peace. ETA’s ceasefire reminds one very potently of the 1998 ceasefire by the IRA, which led to the Good Friday Accords.

Many Brits were naturally reluctant to deal with Gerry Adams and Sinn Fein, who were clearly involved with the IRA, a ruthless terrorist organization. But various actors in Northern Ireland, including leaders like Brit Hume (the Social Democratic and Labor Party) and David Trimble (Ulster Unionist Party), as well as Tony Blair, understood you do not negotiate peace with your friends but your enemies. Once the IRA decreed an unequivocal ceasefire in 1998, it would have been crazy to let the opportunity pass. Yes, it took until 2001 for the IRA to actually start decommissioning their weapons, but the process started in 1998, including the comprehensive agreement for power sharing. The weapons would not have been decommissioned in 2001 if negotiations had not started in 1998.

In Spain, the center-right Popular Party, which scored a number of victories over ETA when it was in government, has been reluctant to become a part of the process. After equivocating, they have now let themselves be dragged only halfway. The overwhelming majority of Spaniards, desperate for an end to the violence, support the process.

Any negotiation will involve ugly concessions. Tony Blair agreed to release hundreds of prisoners in Britain, giving them de facto recognition as “political” rather than criminal figures. And the process in Northern Ireland has faced powerful obstacles, including the suspension of the Assembly born out of the negotiations after a Sinn Fein-related espionage incident a couple of years ago. But this is the price any society has to pay in order to achieve peace when military means are not enough to suppress a violence born out of a historical grudge or a powerful nationalist belief.

I have nothing but contempt for ETA. I have taken part in numerous demonstrations against them in Spain. I still remember the horror of being awakened in the middle of the night by bombs going off near my apartment. But I also understand ETA has challenged the Spanish government to engage in a process that is, at this point, the best option available for a permanent peace.

Ultimately, the solution to the struggle between Madrid and the nationalists will be an expansion of autonomy, even if Spain already allows more regional autonomy than most other European countries. Combating regional nationalism with centralized nationalism only buys you a bit of time. The more power is devolved to the regions and the people in general, the more the tension will be defused. Nationalism has actually been reduced in Scotland and Quebec after they obtained various concessions in recent years. That does not mean giving in to violent separatists but actually sowing the grass under their feet.

An opportunity has opened to shift the discussion away from the language of guns. It should be pursued. The worst that can happen is the process may fail and things will go back to the way they were.