Video games have long entertained users by immersing them in fantasy worlds full of dragons or spaceships. But Peacemaker is part of a new generation: games that immerse people in the real world, full of real-time political crises. And the games’ designers aren’t just selling a voyeuristic thrill. Games, they argue, can be more than just mindless fun, they can be a medium for change.

The proposition may strike some as dubious, but the “serious games” movement has some serious brain power behind it. It is a partnership between advocates and nonprofit groups that are searching for new ways to reach young people, and tech-savvy academics keen to explore video games’ educational potential.

Together they have found some seriously high-powered backers. Last year the MacArthur Foundation began issuing grants to develop persuasive games, including a $1.5 million joint gift to James Paul Gee, a professor of educational psychology at the University of Wisconsin, and GameLab, a New York firm that designs games. Meanwhile the United Nations has released Food Force, a game that helps people understand the difficulties of dispensing aid to war zones. Ivan Marovic, co-founder of Otpor (Resistance) — the Serbian youth movement widely credited with helping to oust Slobodan Milosevic — helped produce A Force More Powerful, a game that teaches the principles of nonviolent strategy. And the third annual Games for Change conference in New York, held earlier this month, attracted academics and nonprofit executives, including several from the World Bank and the United Nations.

“What everyone’s realizing is that games are really good at illustrating complex situations,” said Suzanne Seggerman, one of the organizers of the conference. “And we have so many world conflicts that are at a standstill. Why not try something new? Especially where it concerns young people, you have to reach them on their own turf. You think you’ll get their attention reading a newspaper or watching a newscast? No way.”

Henry Jenkins, an M.I.T. professor who studies games and learning, said the medium has matured along with the young people who were raised on it. “The generation that grew up with Super Mario is entering the workplace, entering politics, so they see games as just another good tool to use to communicate,” he added. “If games are going to be a mature medium, they’re going to serve a variety of functions. It’s like with film. We think first of using it for entertainment, but then also for education and advertising and politics and all that stuff.”

Given away free, they have found astonishingly large audiences. The United Nations game, Food Force, has been downloaded by four million players, a number to rival chart-busting commercial hits like Halo or Grand Theft Auto. In May, MTV’S college channel released an online game called Darfur is Dying in which players escape the Janjaweed while foraging for water to support their village: despite its cartoonish graphics, a strangely powerful experience. In the first month alone 700,000 people played it. Of those, tens of thousands entered an “action” area of the game — political action, that is — where they can send e-mail messages to politicians and demand action on Darfur.

A Force More Powerful is considerably more complex. Players must make dozens of decisions as they try to foment democratic uprisings, but each action brings unexpected consequences. A huge demonstration may get your leaders arrested by the police, a boycott is safer but less effective, and so on.

“The beauty of the game is that players can teach themselves by trying things out,” Mr. Marovic said. The game includes a disclaimer pointing out that not all tactics will work as well in the real world. But “people will learn certain principles,” he said, “like why to start with gentler tactics first and move to more aggressive ones only after you have popular support.”

This is the central conceit behind all these efforts: that games are uniquely good at teaching people how complex systems work. “You could have some big theory about society, but these days it’s like, sorry, people aren’t going to read your white paper on it,” said Ian Bogost, an assistant professor at the Georgia Institute of Technology, whose book on serious games will be published next spring by M.I.T. Press. “Put it in a game, and they’ll discover what you’re talking about themselves.”

Professor Bogost has put that theory in action. In 2003 the Howard Dean campaign hired his company, Persuasive Games, to make a game that showed volunteers how the Iowa primary work was organized . Then the Illinois Republicans paid him to devise four games illustrating their major election planks. In one, you have to ferry sick patients through city streets to hospitals until you discover that the hospitals have become overcrowded. The only way to free more money and space is, hilariously, to enact anti-malpractice-suit legislation. In essence the game takes a cherished bit of Republican ideology and renders it into gameplay.

Douglas Thomas, a professor at the Annenberg School for Communications, is developing a redistricting game in which players try to gerrymander different states. “The election system is rigged to keep incumbents in, but nobody understands it,” he said. His game is intended “to show them how easy it is to game the system. You’ll be able to give it to a first-grade class and let them fix Texas. Then you can say, hey, a 6-year-old can do a more fair job.”

Video games, serious-games advocates say, also possess a persuasive element that is missing from books or movies: They let the player become a different person (at least for an hour or two), and see the world from a new perspective. When Mr. Burak first showed Peacemaker to Israelis and Palestinians, he found that they were most interested in playing as their own “side.” But when he pushed them to switch positions they developed a more nuanced sense of why the other side acted as it did. In Qatar several people told him that “they kind of understood more the pressures the Israeli prime minister has.”

Not everyone agrees with Peacemaker’s basic assumption: that both Palestinians and Israelis want peace. I discovered I could get to a ceasefire by removing settlements while assassinating Hamas militants, a strategy I doubt Israeli hawks would approve of. Mr. Burak said Israeli players complained about the bulldozing of Arab villages; Palestinians felt the game ought to more clearly reward the use of “subtle” measures. Still, he said, Peacemaker (which was designed before Hamas’s electoral victory or the recent Mideast eruption) inspires an unusual kind of debate: an argument about how rule changes can affect society. “That sort of complex thing is precisely what you can do with a game,” Mr. Burak said.

But do these games actually work? Even proponents admit that it’s still difficult to say. “These things are just at the prototype level,” Professor Jenkins said. “We’ve just got one classroom here, one classroom there, where we’ve documented some benefits.” And without more studies documenting the effectiveness of the games, he said, “oxygen’s going to be sucked out of this.”

Ben Sawyer, co-founder of the Serious Games Initiative — a group devoted to promoting the creation of persuasive games — worries that with so many nonprofit organizations rushing to get in on the action, some of the results are simply “bad games ones that are just boring,” he said. “There are a ton of them in this space.” Designing a fun game is hard enough; making it fun and politically nuanced is really tough.

This is why, as Professor Gee put it, some of today’s serious games reflect a simplistic point of view — like America’s Army, the military’s hit game that puts players in a soldier’s boots, or Under Ash, a Syrian-made game that has you play as a Palestinian fighter. “Building morally ambiguous worlds, that’s a lot harder,” he noted. “We’ve won the hype wars. People accept that games can be good for talking about issues. But now we need a killer app.”

When the United States invaded Iraq in 2003, Gonzalo Frasca, a game designer and professor at the University of Copenhagen, felt it was an awful mission that would further destabilize the Middle East. But instead of writing a furious blog entry about it, he banded together with like-minded designers to create September 12, which presents the argument in a game.

September 12 is played in a single, simple screen. You load it up in your browser and see a gang of terrorists wandering through a tightly packed Arab market, all drawn in a colorful cartoon style. You try to bomb them, but every explosion is so overpowered that it accidentally kills innocent bystanders. Relatives are driven by grief and anger to become terrorists themselves. The more you bomb, the more terrorists you create, until the screen is overrun with them. Thus the game presents its argument: Bombing is no way to win the war on terror.

“I don’t really agree with the game on a political level,” said Mr. Frasca, “but it was a way to get people to discuss it.”

September 12, however, does not behave like a regular video game. It does not try to grab you; it’s not even particularly enjoyable. It exists purely to intrigue you long enough so you poke around and figure out the underlying argument: an op-ed composed not of words but of action.

When Mr. Frasca’s September 12 first went online, players sent hate mail accusing him of being soft on terrorists. Even more controversial was the release in April 2005 of Super Columbine Massacre RPG!, in which players become the killers. The designer, Danny Ledonne, had high ideas about it: he chose low-fi effects to avoid gratuitous gore and included actual dialogue from the teenagers to give insight into their troubled minds. But when it was released, in April 2005, it caused a storm of outrage. Families of the victims said it was disrespectful; a Miami Herald writer called it a “monstrosity.”

The game confronts the questions that lurk behind all serious games: Can video games be art? Can they grapple with disturbing issues, or does the act of playing a game inherently trivialize things?

Mr. Frasca suspects the outcry against such games is generational. Many older people find video games so uninteresting that they cannot appreciate the valuable function they might serve. “There is a taboo with playing with fire,” he said. “It’s very strong in our culture. We’ve been told not to play with serious things.”

When MTV released its Darfur game, some Sudanese peace advocates were uneasy. “The question is, does this trivialize Darfur?” said Susanna Ruiz, who helped create the game. “Well, I say that doing nothing or saying nothing about the death of people trivializes it even more. It is a simplification of it? Of course it’s a vast simplification. But there’s an audience that can approach this and think about Darfur that would never pick up a newspaper article on it.”

Or as Professor Bogost pointed out: “It’s like what Adorno said, the idea that it’s barbaric to write poetry after Auschwitz. But you saw this around film too, when it first started: ‘The medium isn’t serious enough to allow for serious discourse.’ I find it somewhat contradictory because people criticize games for saying there’s nothing good in them, nothing serious. But when games try to talk about a serious issue, they say, ‘You can’t talk about that in a game.’”

Mr. Ledonne noted that he had been contacted by a few survivors of the Columbine massacre, and only one disapproved of the project. Richard Castaldo, a student paralyzed from the chest down in the attacks, said in an interview posted at the gaming blog Kotaku that he had played the game himself. While he found it “a mixed message at best,” he also thought that “it gets people talking about Columbine in a unique perspective, which is probably a good thing.”

“Ultimately, a video game is just another medium for artistic expression,” he concluded. “Which is why I like this game in a weird way, because if you are going to play games, why not learn something important in the process?”