News of war usually travels fast. The sound of battle is a warning to those who can hear it, and our instinct is to alert others.

Not everyone involved in a war approves of this. History is full of commanders who would like to "get on with the job" with no interference. Those who instigate conflict desire "good" news above everything else. Families who have someone fighting only want to know the soldier is coming home safe.

Nowadays it is said war comes "live" to our homes. Technology offers the possibility of satellite transmission direct from the war zone, with cameras in troops' helmets, perhaps a tiny drone observing whole armies engaging or a single child in the path of a missile.

The reality of brute warfare usually interferes with technology's potential. The press are frequently not welcome, military coverage is kept confidential, and people at home have myriad reactions to blow-by-blow action – including not wanting to know disturbing details.

In 1914, a remarkably literate public devoured newspapers and illustrated magazines by the million every day. Editors had to meet readers' expectations while maintaining a distinctive voice. The Manchester Guardian, as it was then, was particularly conscious of trying to reflect what society thought about the war, amid a sea of patriotic coverage. It never forgot that life went on – in politics, in the countryside, in the cinema. Inevitably, the military story dominated and the paper strove for witness accounts to supplement the official reports, for all the press were engaged in their own battle with the army and the government. And the press initially thought they might be winning.

More than half a century of battlefield photography since the Crimean war had come to rival the traditional sketches and illustrations. Pictures, surely, would be telling the real tale.

Not exactly, as the new-fangled medium had bowed to authority from the moment Roger Fenton found himself waiting for the mangled wreckage of corpses and the injured to be removed before he set up his tripod in Sevastopol and Balaklava.

That he was there at all was due to the government's outrage at the excoriating descriptions by the Times correspondent William Howard Russell of military incompetence and neglect of soldiers, reports which had shown realistic journalism was not at all to the taste of those in government or the War Office. Nor to all of the public. Good news was wanted and if that wasn't immediately possible, then at least the bad could be omitted.

As the first world war began to unfold into an unimagined scene of carnage, the press found themselves entangled in all the dilemmas journalists still grapple with today. Access to active fighting areas. Arguments about patriotism. Relationship with one's own military. Decisions on realism.

Looking at the wealth of written and pictorial material that has come down to us from 1914-18, it is hard to grasp the restrictions on the reporting at the time. Only six British correspondents were eventually officially accredited. The generals' attitude was summed up by one who insisted reporters should wait until the final outcome, when the generals would tell them who had won.

But even 30 years ago I remember an admiral who had no intention of letting a single journalist within several hundred miles of the Falklands. Today, the Syrian government merely has to announce that the press will be "welcome if accredited officially" for the inference to be drawn that it's open season on the "non-accredited".

Even so, restrictions do not mean scant coverage. There were acres of newsprint devoted to the first world war. Illustrated magazines were printed weekly and monthly. The cinema began to show newsreels and features, with the line between real action, recreated events and staged footage hardly visible.

The tone in the press was robustly patriotic – a sign of the times welcomed by most readers – though dissident voices were published. The book When the Lamps Went Out reflects the duty the Guardian felt to remain true to its convictions – women's rights, conscientious objectors, radical thinking.

In many ways the volume of information (several editions a day) paralleled today's 24-hour news: a constant river of information, some significant, some discursive, some repetitive, the sheer amount slightly lessening the impact of individual stories. Now, as then, there is a desire to be first with news, and undoubtedly this pushes today's correspondents and photographers at a much greater pace. "Breaking news" exists on a second-by-second basis, with snippets of information pasted on to screens heralded by urgent phrases: "News is coming in … we are hearing now … and it's just been reported that …" A huge difficulty for those trying to verify facts amid the chaos of conflict. Being first and being right do not automatically go together.

Taking the temperature of modern consumers of news is more complex than ever. We are more educated, less respectful of authority, much more sceptical of political voices and official announcements. (Though we still cleave to our own nation's press: with the world's satellite news channels easily available, there's not much evidence that the nation channel-hops to see the Russian/Chinese/Arab or even American view of the world – especially when our own military is in action.)

We are still Fenton-like in mainstream media regarding death, killing and grisliness: modern warfare is sanitised both on the ground and back in the newsroom, though the internet is less controlled.

The modern citizen journalist is moving into the same position as the letter writers and diarists of the first world war. Texting is almost equivalent to the millions of letters posted every week from the frontline trenches: frequent, often very brief missives, opinionated and emotional, vignettes of events that perhaps will have greater weight when the whole story is viewed in retrospect.

And those who report wars have perhaps changed most only in the growth in their numbers, leading to more casualties. They still encounter governments, minders and soldiers who wish to bar their way. They still draw back from the bloody consequences of bombing and fighting. Their editors warn audiences of "disturbing scenes" – which in no manner convey the actual horrors of war. Debates arise about "supporting our boys" or "not understanding what has been achieved". As the guns thunder, do you wish to shock your audience – or alert them? Or merely reassure them?

Asked shortly before her death which war she would have liked to have reported on, Martha Gellhorn, half a century of war reporting behind her, told me: "They're all the same: same obstacles, same disinformation, same terrible warfare. You just have to do your best …"

Kate Adie has written the foreword to When the Lamps Went Out, a collection of Guardian reportage from the first world war, edited by Nigel Fountain and published by Guardian Faber on 15 May. To order a copy for £12.99 (RRP £17.99), visit theguardian.com/bookshop or call 0330 333 6846.