The last time Native Americans gathered and the nation noticed was in 1973. That February, after members of the Oglala Sioux tribe failed to impeach their chairman on charges of corruption, they, with leaders of the American Indian Movement, occupied the town of Wounded Knee, South Dakota. It was a final act in the movement’s years-long campaign to compel the federal government to honor tribal treaty rights. Already, Native Americans had occupied Alcatraz Island, in a largely symbolic attempt to reclaim it, and Mt. Rushmore, which had been part of the Great Sioux Reservation until Congress redrew its borders. But at Wounded Knee the movement found its symbolic apex: the U.S. Marshals surrounded the occupiers, evoking the start of the massacre that had killed more than a hundred and fifty Lakota people in 1890. Over months, the standoff escalated. Officers manned roadblocks in armored personnel carriers, and neighboring states lent their National Guards. Both sides traded gunfire. The first man shot was a marshal, who survived but was paralyzed from the waist down. The second was a Cherokee man, who died. The third was Lawrence Lamont, an Oglala Lakota, whose death was the beginning of the end of the occupation.

There are echoes of Wounded Knee in the conflict that has sprung up near the Standing Rock Sioux Reservation, in North Dakota. Since midsummer, thousands of Native Americans have gathered at the confluence of the Missouri and Cannonball Rivers to protest the construction of the Dakota Access oil pipeline, which would cut just north of the reservation border, crossing sacred sites and imperilling Standing Rock’s water supply in the event of a rupture. In July, the tribe filed a lawsuit against the Army Corps of Engineers, the agency that approved the project, arguing that it had failed to consult with the tribe as required by federal law. While the suit has played out in court, the protesters have said that they will stay until the pipeline is stopped, through winter if they must.

Federal officials have kept a careful distance, but what they have not lent in physical force the state has zealously supplied. In August, Governor Jack Dalrymple declared a state of emergency in North Dakota, warning executives at the pipeline company, Energy Transfer Partners, that his administration could no longer “protect their workers adequately.” Roadblocks were erected north of the protest encampment, and sheriff’s deputies escorted school buses through the area. On September 3rd, the conflict reached its highest pitch. Protesters attempted to obstruct E.T.P.’s bulldozers, and in response the company sent in private security officers, who confronted them with pepper spray and dogs. Five days later, Dalrymple deployed the North Dakota National Guard. “You’ve got a tinder box here, sir,” Chris Berg, a local TV news anchor, told him in an interview.

I arrived at the Standing Rock encampment the following evening with Lissa Yellowbird-Chase, a member of the Mandan, Hidatsa, and Arikara Nation in North Dakota, who had been attending the protests nearly every weekend since mid-August. Tents and tepees sprawled along the banks of the Cannonball River; Yellowbird-Chase’s uncle, who joined us, joked that they reminded him of “powwows in the old days, when we came by travois”—horse-drawn sleds once used by the Plains Indians. Earlier that day, the protesters had won their first major victory. After a judge ruled against the Standing Rock Sioux, the Obama Administration intervened, announcing that the pipeline would not be permitted onto the federal land beneath the Missouri River until the tribe was properly consulted. In the coming months, the Corps will reassess the impacts of the pipeline and meet with tribal leaders regarding this and other infrastructure projects. The Administration also requested that E.T.P. pause work on private land within twenty miles east and west of the river, but this was only temporary: on October 9th, a federal appeals court again ruled against the Standing Rock Sioux, allowing construction on private land to continue. (The next day, the Administration renewed its stop-work request.)

Yellowbird-Chase set up camp by a grove of cottonwoods, for relief from the late-summer heat, and, beneath a tarp, hung a tin can containing cedar leaves and coals from a neighbor’s fire to cleanse the site with smoke. The next morning, we set off for the main part of the encampment. I wondered whether the pause in construction would prompt people to leave, but it became clear, as we approached a mass of tent canopies, that the protest was still growing. Men and women unloaded donations from the trunks of cars—boxes of squash, bags of warm clothes—and passed them with cheerful efficiency down a line of volunteers. Others chopped firewood, hauled trash, peeled vegetables, and fed horses. I unloaded some donations and then joined Yellowbird-Chase for lunch. (It was important, she said, that “we eat with the people.”) As we stood in line, friends and strangers stopped to chat. Many would greet us like this throughout the day, including an elderly white man who was handing out red feathers and who explained, timidly, that he’d dreamed of the protests before he’d come and, in this dream, had handed out red feathers. “That’s cool,” Yellowbird-Chase said, and stuck one in her hair.

Over the weekend, the encampment continued to swell with new visitors. Aztec dancers came from Minneapolis, then delegations from the Round Valley Indian Tribes in California, the Jemez Pueblo in New Mexico, and the Blackfeet Nation in Montana. They entered through a corridor lined with the flags of hundreds of other tribes who had offered support. These arrivals, which happened every day, signified as much a coming together of old enemies as of old friends. Weeks earlier, the Crow, who aided the U.S. Cavalry in its nineteenth-century battles against the Sioux, had come with blankets, coolers of meat, and a horse trailer full of cordwood.

The shared history that brought these tribes together is, of course, more recent than the massacre at Wounded Knee. In “Custer Died for Your Sins,” a manifesto of the Native American-rights movement from 1969, the Sioux historian Vine Deloria, Jr., observed that, although “people often feel guilty about their ancestors killing all those Indians years ago,” the twentieth century had in fact “seen a more devious but hardly less successful war waged against Indian communities.” Deloria was referring to a host of injustices: the lack of funding for tribal education, which forced parents to send their children to government-run boarding schools; the termination of federal recognition for scores of tribes, which caused the loss of services promised by treaty; and a disregard for the sovereignty of tribes, manifest in the building of infrastructure on Indian land without honest consultation or consent. In Deloria’s time, that infrastructure was dams, which flooded forests and farmland on many reservations, including Standing Rock. Today, as Dave Archambault II, the tribe’s chairman, suggested in an editorial for the Times, that infrastructure is pipelines. “Tribes have always paid the price for America’s prosperity,” he wrote.

Most days, protesters march or caravan to nearby construction sites to dance, sing, and engage in prayerful ceremonies. When I was there, though, they stayed home, buoyed and exhausted by the turn of events. In the catharsis of the encampment, it would have been easy to forget the anxiety present just to the north, were it not for the surveillance helicopters circling daily overhead. As one hovered low over the encampment one evening, Yellowbird-Chase said wryly, “They’re making sure we’ve had our three meals today.” Some found these intrusions funny, as if the state were a petulant little brother, taking his games too seriously. I, and others, found them dissonant and unsettling. One morning, I ventured out to the pipeline route, on dirt roads through open pasture, and came across eight vehicles, six of them law enforcement. Another belonged to a local rancher, who told me, “When you see cars full of people and no license plate and bats in the back, you fear for your family.” I asked whether he was willing to stay and talk longer. “No,” he said. “It’s too dangerous.”

Police form a line during protests near Standing Rock on October 5th. Photograph by Terray Sylvester / Reuters

When people compare Standing Rock with Wounded Knee, they note that, at the height of the 1973 occupation, there were several hundred protesters; now there are several thousand, owing in part to social media. But there is another important distinction, which is that the movement has largely committed itself to nonviolence. At least ninety people have been arrested so far for acts of civil disobedience—trespassing on construction sites and locking themselves to bulldozers—but none were carrying weapons or behaving violently. In the confrontation on September 3rd, six protesters were bitten by dogs, and one security officer was pinned against his truck, then let go without injury. (The rancher I met, who said he witnessed the skirmish, claimed that he had seen Native Americans armed with tomahawks.) The protesters have taken to calling themselves “protectors,” a semantic distinction that can sound a little hokey until you recall the historical stereotypes of savagery that they are laboring against.

On September 25th, protesters returned to the construction site to plant corn and willow trees in the pathway of the pipeline. Sheriff Kyle Kirchmeier told the local press that a security guard was assaulted, sustaining minor injuries, and a protester was spotted with a gun. (Kirchmeier’s office did not supply evidence of either claim, and no arrests were made.) Then, on September 28th, in perhaps the most troubling confrontation so far, officers surrounded a group of protesters, holding loaded rifles. The protesters threw their arms in the air, shouting, “We have no weapons! We have no weapons!” Both sides retreated unscathed, but it was a deaf and reckless nod to history on the part of the state. And it made me wonder whether the weapons that officers have seen are imagined, a way to give form to the fear that the protest inspires—the fear not of violence but of a people who have survived, who remember things the rest of us often choose to forget, and who have found each other, again, through this memory.