In his opening chapter, Hoffman writes of the effects of Capital to Capital: “Satellite television literally breached the two countries’ ideological and geographic borders, allowing viewers to eavesdrop on conversations between their political leaders.” Since that time, much has changed culturally and technologically, but while “communication technologies have evolved dramatically in the following three decades,” he writes, “media continues to be the most powerful force for social change the world has ever known.”

Hoffman spends the rest of Citizens Rising proving that point, in three well-organized parts. He begins by exploring the utility of media, using the Cold War broadcasts as one example of how a technological medium was used to act as a forum that could breach physical and ideological distance. From there, he makes the point that technology does not, by itself, equate to the freedom of information. In the wrong hands, as was the case in the Rwandan genocide of 1993-94, technological mediums can be used as weapons not just of oppression but of mass murder. In that instance, Radio Télévision Libres des Mille Collines, along with other outlets, fueled the genocide, spewing racist ideology and violent messages, ultimately provoking and cheering on Hutus to murder Tutsis. “Concentrated in the hands of demagogues,” writes Hoffman, “media can foment hatred, atrocities, and war.” Finally, Hoffman closes the book with a series of stories that show how digital media and mobile phones are proving to be powerful tools against authoritarian regimes.

In Afghanistan’s recent history, Hoffman shows readers how a lack of media—after being squashed by a governing authority-can silence dissent and fog public understanding. He also lays out how a resurgence of media, through technology, can restore the voice of a people.

After the Taliban had been all but ousted from the country in 2001, following five weeks of direct, targeted bombing, images of Afghan citizens dancing in the streets, shooting guns into the air, some shaving their beards in retaliation against a Taliban law made their way into TV sets around the world. That is, everywhere except Afghanistan. Hoffman writes:

Other than what unfolded in front of their eyes—fragments of reality, often scary, usually without explanation or context—the people most affected had little clue as to what was going on. There was no Afghan newspaper sporting the headline ‘Taliban Gone!’ for the simple reason that local newspapers didn’t exist. . . . It is a fair bet that . . . you knew more about what was going on in 2001 than those in Afghanistan who were shaving their beards or flying their kites or wondering if they would survive the night.

Some news seeped in from international broadcasters, but many areas outside of Kabul existed in “media darkness,” writes Hoffman. And so Internews, with funding from the Office of Transition Initiatives (part of the United States Agency for International Development), set about building FM stations in those districts.

The journey since has been steady but slow. Most of the media growth in Afghanistan has come from mobile phones. In 2012, when Hoffman was writing Citizens Rising, only 4 percent of Afghans had internet service, due primarily to the outrageous fees to set it up (in 2012 Kabul it cost about $1,000, while the gross national income that year was only $680 per capita). Yet at the same time, there were 20.4 million cellphone users out of a population of 29 million. Mobile tech was responsible for 15 percent of government revenue, and it’s helped transform a cash economy into one that banks primarily with cellphones.

The change has marked a crucial cultural shift in the country, Hoffman writes. Access to information makes the citizenry safer, since communication between security forces and villagers makes it harder for terrorists to exist undetected. But perhaps more important is “the need for recognition,” he writes. “The need to be seen for who one is and what one thinks, is the core of human dignity. When people in a country like Afghanistan can hear their voices and express their opinions without fear, it transforms the culture.”

We now exist in an era in which nearly everyone has an opportunity to become a part of the media. With information and access in the hands of many, it’s harder for the powerful few to exercise media manipulation. There is perhaps no better example of this global culture shift than the Arab Spring, in which a groundswell of Facebook users ultimately toppled a dictatorship, forcing Egyptian President Hosni Mubarak to step down from office. The message to be learned from the events that now fall under that name is that the revolution wasn’t caused by Facebook, Hoffman writes, but by people. Facebook was merely the medium. “Technology by itself does not cause revolutions,” he writes, “people do.”

Christie Chisholm is an associate editor and production editor at CJR. Follow her on Twitter at @c_chisholm.