It is a commonly-held view in Washington these days that the advent of instantaneous and global satellite technology has given the news media more of a voice in international affairs than ever before.

Diplomats call it the CNN Effect, and the term is not a compliment. It suggests that when CNN floods the airwaves with news of a crisis from abroad, policy makers have no choice but to redirect their attention to the latest disaster zone. The term CNN Effect also has a slight sinister cast to it, suggesting that the television pictures will provoke an emotional outcry from the public to "do something" about the latest incident, whether such action is warranted or not.

When I first set out to write my book, "Lights, Camera, War: Is Media Technology Driving International Politics?," I too held the view that media technology was driving foreign policy.

I remember standing in an Air Force hanger in Saudi Arabia a few days before the Persian Gulf War began, watching Secretary of State James Baker deliver an ultimatum. With cameras rolling, Baker told 400 cheering U.S. airmen and airwomen that we were on the brink of war, that unless Saddam Hussein withdrew from Kuwait, the allies would go to war with Iraq.

Baker told me later that he wasn't talking to the soldiers, and he wasn't talking to us journalists but rather he was talking to one man, Saddam Hussein, sitting in his bunker in Baghdad, watching on CNN. It was easier and more reliable for Baker to deliver his message on CNN than through any diplomatic pouch or personal envoy.

I set off to write a book on the information revolution. I began to read history, to see how other inventions, other new media technologies, had changed the political landscape of their time. And in the process of reading history, I discovered a pattern. Whenever a new media technology arrived on the scene -- from the printing press to the Internet, from the telephone to the photograph -- the new invention produced virtually the same result.

Diplomats complained that the new invention robbed them of sufficient time to think, that it tethered them more directly to their capitals. I am particularly fond of an anecdote about British envoy Arthur Buchanan, who was asked in 1861 to assess the telegraph's impact on diplomacy. "It reduces, to a great degree, the responsibility of the minister," he lamented. "For he can now ask for instructions instead of doing a thing on his own."

In every era too, journalists boasted that the new media technology gave them more power and influence than ever before. William Randolph Hearst, publisher of the sensationalist New York Journal, sent one of his illustrators to Havana to drum up interest in what would eventually become the Spanish-American War. The artist, Frederic Remington, was disappointed in a lack of action in Cuba.

"Everything is quiet," he telegraphed Hearst, using the latest technology to speed his message. "There is no trouble here. There will be no war. I wish to return." To which Hearst replied, in a cable that may be apocryphal but clearly demonstrates his view of journalism's impact on diplomacy: "Please remain. You furnish the pictures and I'll furnish the war."

The generals tended to adore the new technology, understanding that speed of information delivery was critical to their victory. How often have you read of battles fought and lives lost after treaties had been signed in home capitals? Speed of information was an asset to the generals.

William Tecumseh Sherman, the Civil War general, loathed the press and threatened reporters with court martial if they appeared at his camps, nevertheless valued the telegraph that speeded both news copy and battle information. "The value of the magnetic telegraph in war cannot be exaggerated," Sherman wrote in his memoirs. "Hardly a day intervened when General Grant did not know the exact state of facts with me, more than 1500 miles off, as the wires ran."

Of course speeded information also gave political leaders a chance to influence battle. Abraham Lincoln was a frequent visitor to the White House telegraph, awaiting, sometimes futilely, word from his recalcitrant generals that a battle had been joined.

In every generation, too, politicians groaned that their orations had been cut to soundbites. In 1889, the London Spectator lamented the telegraph's impact on politics. "The constant diffusion of statements in snippets, the constant excitements of feeling unjustified by fact, the constant formation of hasty or erroneous opinions, must in the end, one would think, deteriorate the intelligence of all to whom the telegraph appeals."

Then as now, critics despaired at the changes required by a new technology. Present-day predictions that an age of computer information will make the television networks obsolete have their echo in earlier clashes of technology and media power.

There is even precedent on the economic front for the current debate over who will benefit from the Information Highway, with social scientists of various stripe debating various questions. Often there were economic reasons for the resistance. The turf-conscious chief engineer of the British Post Office, testifying before a committee of Parliament, was asked if the telephone merited attention. "No sir," he said. "The Americans have need of the telephone, but we do not. We have plenty of messenger boys."

Among the intellectuals, the fear was that new technology would somehow dilute the quality of public discourse. Among the politicians, the fear was that it would empower the public. Soon after the Russian Revolution, Joseph Stalin rejected a proposal from Leon Trotsky to build a modern telephone system. "It will unmake our work," he said. "I can imagine no greater instrument of counter-revolution in our time."

To this day, the phone system in the former Soviet Union is a disaster, and many local governments and businesses have leapfrogged a generation of technology, skipping the burden and expense of land phone lines to go straight to cellular.

At one point I thought of calling the book Echoes, because every time I went to the library there were echoes in the history, echoes of the issues we are dealing with today in the CNN Effect. But soon enough I began to realize that for all these marvels, what changed when a new invention intersected with the political world was not the substance of a message but its speed and method of delivery.

Baker, standing in that hanger in Saudi Arabia, understood this. He understood that CNN gave him a new tool for sending a message, but that its contents still depended on a thoughtful policy. In short, I began to develop a corollary theory, that for all the demands and annoyances of a new media technology, political leadership mattered more.

Some leaders excelled at using a new invention that happened on their watch. One only has to listen to Franklin Roosevelt's Fireside Chats to understand the power of conquering radio. Others tripped and fumbled their way around a new invention. Poor Lyndon Johnson never could master television to make his case to the country about Vietnam. Some people said his ears were too big, his glasses too small, his hair too thin. Others said the war was wrong, or at least poorly planned. Either way, television like all the other inventions gave the public more of a voice, and demanded of leaders that they prove their case by the latest available means.

Another finding was that every new invention tended to produce a period of less than stellar journalism, a time of experimenting with the new technology to test the bounds of taste. There is no worse chapter of American journalism than coverage of the Civil War, abetted by the telegraph.

The telegraph allowed reporters covering the Civil War to distinguish themselves as sensationalists. Exaggeration became the hallmark of Civil War journalism, complete fabrication not at all uncommon. One correspondent begged a wounded officer not to die before he had finished interviewing him, promising him his last words would appear in "the widely-circulated and highly influential journal I represent."

Circulation skyrocketed as newspapers discovered they could sell five times their nominal run with details of a battle. Reporters often bribed telegraph operators to give preference to their copy over a competitor's. And publishers, much like today's TV talk show producers, clamored for more. "Telegraph fully all news you can get," Chicago Times editor Wilbur F. Storey ordered a reporter, "and when there is no news, send rumors."

There was one other lesson in the history, and it dawned slowly. Conventional wisdom holds that photographs tell a thousand words, that one picture can galvanize a nation to action. We think of the photographs that became icons for the anti-war movement in Vietnam -- naked children running from napalm, General Lo-wan shooting a Viet Cong ambusher. We think of that photograph on November 9, 1989, the night the Berlin Wall fell, the dancing atop a symbol of repression.

We think of the pictures from Somalia, where is it widely believed that pictures got us in and pictures got us out. Videotape of starving Somalis on CNN forced President Bush to send in the Marines, goes this refrain, and pictures of an American corpse being dragged through the streets of Mogadishu by gleeful Somalis forced President Clinton to bring the Marines home.

But the truth is more textured, and deserves some respect. Bush got into Somalia in part because he wanted to leave office a humanitarian. Clinton got out in part because he had escalated the conflict from a humanitarian mission to something it was never designed to be, a manhunt for one warlord whose supporters grew ugly toward the Americans.

I began to understand, in short, that captions count. It matters what the public thinks when it sees the photographs, what it understands of the conflict in question, and that's where our role as journalists has changed little in the last 500 years.

Those pictures of a body dragged through the streets of Mogadishu, in a different time, might have evoked a different response. Americans might have found them grounds for avenging the wrong, for staying to finish the fight. Instead, we came home. It matters what interpretation governments and humanitarian groups and yes, the news media put on those pictures.

No better example exists than Tiananmen Square, where in 1989 Chinese students demonstrated for democracy. Who can ever forget that photograph of a single protester, his white shirt flapping in the wind, standing in front of a tank? In the West that photograph became a symbol of one man's defiance against tyranny. But in China authorities put the same photograph on display with a different caption, one that credited the restraint of the Chinese troops in not mowing down their fellow citizens. It is hard to know if that interpretation was accepted by the Chinese who saw that photograph on exhibit, but it is surely a different way to look at the picture.

The idea that context mattered seemed to suggest that individuals can make a difference, that technology is not determinative. Oh yes, it leaves its pattern, it unleashes great shock waves of change in the way in which information is relayed, and it forces political figures to learn new methods of communicating. But technology does not dictate outcomes.

Marshall McLuhan, a media guru of the 1960s, liked to say that the medium was the message, that it didn't matter what the television anchor said, the pictures behind him told their own story. Well Marshall McLuhan was wrong. It does matter what the caption says. It matters what people say about a photograph and what they write about it. It matters what people hear about it and what they think they saw. Technology changes everything about the way in which we experience information, but leaves for us the way in which we use it.

There is no better precedent for the changes unleashed by satellite television than the upheaval delivered by the telegraph. Quite simply, the telegraph ushered in a revolution in the way international relations were conducted. From an age when messages were delivered at the speed of transportation -- a horse, a sailing ship, a train -- diplomats braced themselves for what they considered instantaneous communication.

The shift was almost beyond imagining. Samuel F.B. Morse, inventor of the telegraph, marveled: "We can speak to and receive an answer in a few seconds of time from Hong Kong, where 10 p.m. here (New York) is 10 a.m. there. China and New York are in interlocutory communication. We know the fact, but can imagination realize it?" But soon enough the political system absorbed the demands of the new technology, and the photograph and film and radio came to make new demands of policy makers and journalists.

Well I believe that in 1996 the CNN Effect has lost its punch. I do not think, if pictures of starvation in Somalia came across our airwaves today, I do not think the public would rise up and demand intervention. Call it compassion, fatigue or inoculation to the shock, but I think the political system has absorbed the changes satellite television demanded.

Now it is on to cyberspace, where governments will be competing against media organizations and special interest groups and even terrorists for the attention of viewers. To a generation that thought the train was a vast leap in the speed of delivering a message, the telegraph seemed unabashedly a revolution. So too for a generation that thought CNN represented the ultimate in delivery of real-time information. The future is much more daunting.

A word about volume. Digital technology will carry more information than any invention gone before, a testament to the ingenuity of inventors to crash through the parameters of imagination. At first this seems an anomaly, since the telegraph, telephone, radio, television, and computer messages all travel at the same speed. But once the computer receives a message, it can download a larger quantity of material in a minute than any other medium. The speed of information relayed is the same, but the volume of information conveyed is bigger.

To a generation that thought the train was a vast leap in the speed of delivering a message, the telegraph seemed unabashedly a revolution. So too for a generation that thought CNN represented the ultimate in delivery of real-time information.

What's coming is a revolution. Glass fibers will be able to carry at least 150,000 times as much information as the standard copper wires now used to connect the computer to a modem. An hour's worth of digital video will be delivered in seconds.

The speeded dissemination of information has just begun. And with it will come new challenges for government, for armies, for journalists. I believe it will be harder for our leaders to conduct a national conversation in cyberspace. They will be competing against special interest groups and media powerhouses and even direct messages from terrorists for the public's attention. But it is up to individuals to try.

Stripping away the awe of novelty and the excitement of invention, there is simply nothing in technology's charter to suggest the fundamentals will change in the next generation, when diplomats communicate with the public by computer and viewers sign on the Internet to customize their own version of history.

There is magic in the technology and wonder in its results. There is speed in delivery and an information explosion. There is a new day for diplomacy, a novel outlet for public opinion, and a steep test for journalism. Above all, there is a challenge to leaders to exploit the new inventions. But technology gives no odds on its use. That is for people to determine, leaders and their publics, you and me, individuals all.

Johanna Neuman is foreign editor of USA Today.