On a Tuesday evening, two weeks after Election Day, about a hundred people congregated at Noisebridge, which describes itself as a “a hackerspace for technical-creative projects,” in San Francisco’s Mission District, for a workshop called “Trump Preparedness: Digital Security 101.” It was just one of many digital-privacy-and-security workshops that have popped up around the Bay Area—in living rooms, offices, and community spaces—ahead of the Presidential Inauguration, in January, and a national-security-and-surveillance apparatus helmed by Donald Trump.

Housed in a creaky loft above a grocery store called Mi Ranchito Produce, Noisebridge is a neo-cyberpunk, anarchistic, community-friendly clubhouse. “Thank You for Being Excellent & Hack the Planet” was painted on a wall near the entrance. Waves of colored light drifted over the surface of a room divider, which was made of L.E.D.-stuffed beer bottles. Murals of Nikola Tesla and Margaret Hamilton, the computer scientist who wrote flight software for NASA’s Apollo program and coined the term “software engineer,” stretched across one end of the room, facing a wall of books with titles such as “Silicon Snake Oil” and “Stealing the Network: How to Own a Continent”__ and a wall-mounted red telephone with a handwritten plaque reading, “The interhackerspace PBX starts here.” I stood behind a bookshelf and surreptitiously Googled “PBX” on my iPhone. (It stands for “private branch exchange,” and, the sign claimed, would be used to connect “every hackerspace in the world” via a voice-over-I.P. network.)

John Shutt, a journalist and one of the event’s organizers, was taking care of some last-minute details over by a spread of pizza and soda, which had been donated by Keybase, a service for sending encrypted messages. “I was horrified after Trump was elected,” he told me. Shutt, who is in his mid-twenties, willowy, and blond, said he is especially concerned about undocumented immigrants, Black Lives Matter activists, members of the L.G.B.T.Q. community, and people working in the marijuana industry, who, he said, would be at risk if Jeff Sessions becomes Attorney General. Shutt was also nervous about doxxing, an online-harassment tactic that entails publishing a target’s personal information, which he feared has the potential to become a more widespread practice among online trolls and vigilantes emboldened by the Trump Administration. “We’ve got a couple of months,” he said. “The people that are in the most jeopardy now can start to get prepared. It’s like battening down for a hurricane.”

Shutt stood in front of the room with a microphone. “If you want to be as secure as possible, you should probably throw your computers and phones in the bay right now,” he said. “But if you want to organize against Trump it’s going to be hard to do it without a phone.” Shutt asked the attendees to close their eyes. “Picture what great things you’re going to do over these next four years, despite the Administration that’s coming into power, and what might stop you from doing that,” he said. “If you’re going to organize, what kind of tools do you need to organize? What can people do to spy on you, and what can you do to prevent that?” I looked around the room; everyone but Shutt had their eyes open.

The evening’s agenda was loosely based on the Electronic Frontier Foundation’s Surveillance Self-Defense Guide: workshop topics included installing the encrypted chat app Signal; downloading the Tor browser; password management; hard-drive and device encryption; setting up two-factor authentication; and exporting data to keep from storing too much in the cloud. “You’re probably not going to withstand an attack from a state-level actor,” I heard someone say as I circumnavigated the room. “But you can try to make it not worth their time.” People discussed their “threat models,” the individualized worst-case scenarios against which they would need to fortify themselves, and the kinds of ideas about digital privacy and security that have been circulating over social media and in online how-to guides like “A DIY Guide to Feminist Cybersecurity,” “Securing Your Digital Life Like a Normal Person,” and “A First Look at Digital Security.” A woman named Ruth Miller started the password-management workshop with an explanation of the password-management tool 1Password. “I have never known them, I will never know them, they’re unknowable,” she said, of her passwords.

Sitting back from the group, near the 3-D printing station, was a security researcher visiting from Berlin for the Thanksgiving holiday, who, like most people one encounters at a privacy workshop, declined to give his name. Skinny and dressed in all black, he was folded around a ten-year-old I.B.M. ThinkPad, which sported an external signal board—running Linux, an open-source operating system—dangling off the side. He seemed unimpressed with the uptick in digital-security awareness since Trump’s election. “Those of us who have been advocating the use of privacy technology for years, even before Snowden, are amused,” he said. “It’s refreshing, I guess, to see such interest all of a sudden, on the basis of the Trump Presidency, but . . . ” He palmed his chin. “How do I say it? The Obama Administration, as Michael Hayden said, kills people with metadata.”

A middle-aged civil engineer wearing a fleece vest from the Leadership Institute told me he had come to the workshop simply to learn. Having come from India thirty-three years ago, he was worried by the rhetoric of the Trump Administration, particularly that which targets immigrants and Muslims. “I’m not super-duper activist, or out there in the society,” he said. “Personally, I have nothing to hide, I’m not doing anything wrong, I’m not illegal. I’m not afraid in that sense. But it’s just concerning, you know, that you hear this kind of talk from these people. You don’t know how far they go.”

No matter how innocent people consider their own behavior, the security researcher from Berlin said, the possibility of being surveilled can have a chilling psychological effect. Even the most ordinary things can feel embarrassing. “People who say that they’re doing nothing wrong and have nothing to hide—I often ask them if I can have a copy of their Web-browser history. Only one person has ever said yes.”