Harold Evans: Intelligent, traditional media are crucial to the defence of our liberty

Revelations about the 'News of the World' had not been exposed when Cebrián was writing about how some journalists had become spies, informers and smear artists

Has the advent of social media doomed dictatorships to short lives?

It is a nice thought, encouraged by the revolutions in Tunisia and Egypt, facilitated by digital activists, but the double fist of shutting down the internet and hammering the people on the streets has kept the authoritarians in control in Belarus, in Thailand, in China and Iran.

Where there are genuine grievances, we tell ourselves the pabulum of official propaganda cannot gainsay thousands – millions! – of people sharing information and then a few keystrokes of text messaging can summon a mass protest. It is too early to guess what will happen in Libya or Yemen. It is chilling to note that after everyone got excited about the uprising in Iran, the very social media we applauded made it easier for the repressors to trace and bash the bloggers: "We know where you live..."

It is true that in our digital age, discontents no longer simmer. They erupt. "I can call spirits from the vasty deep," said Glendower in Henry IV, and today there'd be no Hotspur to ask, "But will they come when you do call for them?" They will come when a free flow of information blows the lid off a totalitarian society. But while we celebrate digital activism, let's not forget that intelligent and resourceful traditional media can be just as crucial in the defence of liberty. It is not axiomatic that the street protests facilitated by Facebook, Twitter and texting will produce a responsible democracy. That requires a steady flow of reliable information not compressible into 140 characters; it requires leadership and respect for the rule of law.

Spain is a timely case in point. We take it for granted that it's a stable, vibrant democracy. We should remember when it wasn't; for a start, when General Franco led a nationalist coup against the elected Republican government. Franco was more of a hard-line conservative authoritarian than a fascist, but ran the country with an iron fist for 36 years, violently suppressing dissent and censoring the press. Gradually, in the exigencies of the Cold War, a prospering Spain was welcomed back into the Western community of nations, and at the end of his life Franco redeemed himself in the eyes of many by arranging an orderly transition to rule by King Juan Carlos. The king at once instituted a parliamentary democracy and Spain lived happily ever after. Not exactly.

Only five years after Franco's death, Spain's fledgling democracy was once more threatened by a military coup. The multitudes of visitors to Spain who feel the reverberations of history in Madrid and Barcelona and Granada and Cordoba, capital of the Islamic caliphate, probably haven't a clue about 23 February 1981, as relevant to Spain's history as any stone monument in a city square. A lieutenant colonel, one Antonio Tejero, burst into the elected Spanish Congress of Deputies supported by 200 armed officers. They sprayed the ceiling with submachine-gun fire and informed the terrified deputies crouching on the floor that they were hostages pending the arrival of an official to acknowledge the colonel and his plotters as the new rulers of Spain. Tanks were on the streets in Valencia. Madrid's radio and TV station was seized by the plotters, and duly announced their triumph. Spanish democracy was over again.

Well, not yet. Two important institutions stood between the plotters and a return to authoritarian rule for heaven knows how long this time: King Juan Carlos and the press. And by the press I mean pre-eminently El País, the newspaper edited by Juan Luis Cebrián. That evening he got out a special edition of his paper. It reported what had happened and carried a biting condemnation on the illegality of the coup, a call to the country to stand by king, constitution and democracy.

They rushed copies to the king. A copy reached the chamber where Tejero stood at the rostrum with his gun. One of the beleaguered deputies, Javier Solana, remembers breathing more easily when he looked up, astounded to see Tejero holding a copy of El País. Tejero might as well have been holding a grenade with the pin out; he was in effect reading his political obituary. His co-plotter, an insurgent general who was supposed to take firm control of television and radio, lost his nerve. About six hours after receiving the edition of El País, the king in full military regalia was able to appear on national television and denounce the plotters.

The story of the coup that collapsed is as important in any history of the press as Watergate or the Pentagon papers, but too little known outside Spain. Thirty years after the coup, Cebrián chooses not to relate his heroic role, but it forms a backlight to his thoughtful essays on the press. His sketch of how news and comment were managed in a military dictatorship has a comic-opera quality it did not have in its heyday. Maybe even then, by comparison, say, with the way they went about these things in North Korea and Brezhnev's Russia, Spanish insouciance took some of the venom out of the sting, but it was certainly stultifying. Only the Government could authorise a newspaper; publishers had to be licensed. "Apart from intellectual delirium," as Cebriá* puts it, censorship worked like a bureaucratic machine... Executive editors were appointed by the minister and everything published – news, photographs, advertising – had to pass official inspection. It was unthinkable, of course, that Franco could ever err.

The transition to democracy was awkward. Spain at all levels had only the vaguest notions of how the freedom the king ordained worked or was supposed to work, how the country could advance at all when ills could be ventilated, wielders of power held accountable, reputations assailed. The press, which had learned to live in authoritarian society but never lost its ideals, was the only institution really capable of teaching democracy to people who had never lived in a democracy. The trade unions had been forbidden, the judiciary and other social institutions were ineffectual, economic forces were weak, and the military leaders were confused. El País became a forum for debate and conciliation, a symbol of the transition. Cebriá* notes that its subsequent professional and commercial success "is still resented in certain circles".

Cebrián is no mere booster. He is caustic about corruption of the ideals that animate responsible journalism. The perversion of investigative journalism, especially on Spanish television, he calls "a curse of our time".

The revelations about how Rupert Murdoch's News of the World found a way into private voicemail messages had not been exposed when Cebrián was writing furiously how some journalists had become spies and informers, gross invaders of privacy, smear artists in the vein of Joe McCarthy. It's not a Spanish custom. It is an international plague, manifest in particular in obnoxious websites that trade in abuse and paranoia, "their arbitrariness unchecked".

And that kind of conduct is as much a danger to a democracy as any strutting general.

Harold Evans was editor of 'The Sunday Times' (1967-1981) and 'The Times' (1981-1982). This essay is a version of his foreword to 'The Piano Player in the Brothel' by Juan Luis Cebrián to be published by Duckworth on 10 March