The Arab uprisings of 2011 are like the European revolutions of 1848—complicated and messy.

"Each revolution must be assessed in its own context, each had a distinctive impact. The revolutions spread from one point to another. They interacted to a limited extent. … The drama of each revolution unfolded separately. Each had its own heroes, its own crises. Each therefore demands its own narrative …"

That could be the first paragraph from a future history of the Arab revolutions of 2011. In fact, it comes from the introduction to a book about the European revolutions of 1848. In the last few weeks, quite a lot of people—myself included—have drawn parallels between the crowds in Tunis, Benghazi, Tripoli, and Cairo and the crowds in Prague and Berlin two decades ago. But there is one major difference. The street revolutions that ended communism followed similar patterns because they followed in the wake of a single political event: the abrupt withdrawal of Soviet support for the local dictator. The Arab revolutions, by contrast, are the product of multiple changes—economic, technological, demographic—and have already taken on a distinctly different flavor and meaning in each country. In that sense, they resemble 1848 far more than 1989.

Though inspired very generally by the ideas of liberal nationalism and democracy, the mostly middle-class demonstrators of 1848 had, like their Arab contemporaries, very different goals in different countries. In Hungary, they demanded independence from Habsburg Austria. In what is now Germany, they aimed to unify the German-speaking peoples into a single state. In France, they wanted to overthrow the monarchy (again). In some countries, revolution led to pitched battles between different ethnic groups. Others were brought to a halt by outside intervention.

In fact, most of the 1848 rebellions failed. The Hungarians did kick the Austrians out, but only briefly. Germany failed to unite. The French created a republic that collapsed a few years later. Constitutions were written and discarded. Monarchs were toppled and restored. Historian A.J.P. Taylor once called 1848 a moment when "history reached a turning point and failed to turn."

And yet—in the longer run, the ideas discussed in 1848 did seep into the culture, and some of the revolutionary plans of 1848 were eventually realized. By the end of the 19^th century, Chancellor Otto von Bismarck had indeed united Germany, and France did establish its Third Republic. The nations once ruled by the Habsburgs did gain independence after World War I. In 1849, many of the revolutions of 1848 might have seemed disastrous, but looking back from 1899 or 1919, they seemed like the beginning of a successful change.

In the Arab world, we are also watching different kinds of people with different goals take charge of street demonstrations, each of which must certainly be assessed "in its own context," as the historian wrote of 1848. In Egypt, decisions taken by the military may well have mattered as much as the actions of the crowd. In Bahrain, the conflict between Sunnis and Shiites is clearly central. The role of "Islam" is not the same in countries as different as Tunisia and Yemen. In Libya, the regime has already shown itself willing to use mass violence, which others have avoided. Tempting though it will be to lump all these events together and to treat them as a single "Arab revolution," the differences between countries may turn out to be more important than their similarities.

It is equally true that by 2012, some or even all of these revolutions might be seen to have failed. Dictatorships might be reimposed, democracy won't work, ethnic conflict will turn into ethnic violence. As in 1848, a change of political system might take a very long time, and it might not come about through popular revolution at all. Negotiation, as I wrote a few weeks ago, is generally a better and safer way to hand over power. Some of the region's dictators might eventually figure that out.

Besides, thinking about 1848 provides a useful sort of balance. There was a moment, at the height of the Cairo demonstrations, when I found myself sitting in my living room, watching Hosni Mubarak address the Egyptians in real time. I could see him speak, hear the translation, watch the crowd's reaction: For a moment, it was possible to imagine that I was watching the revolution unfold in real time. But of course I could only see what the cameras were showing, and much of what was important was invisible—the men in uniforms negotiating behind the scenes, for example.

Television creates the illusion of a linear narrative and gives events the semblance of a beginning, a middle, and an end. Real life is never like that; 1848 wasn't like that. It's useful to ponder the messiness of history from time to time, because it reminds us that the present is really no different.

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