WASHINGTON — A group of Democratic operatives were repairing to a luxury golf resort near Miami on Friday to plot an opposition strategy to Donald J. Trump. Scores of others were deserting the nation’s capital for tropical beaches or woodland cabins without internet access, the better to distract themselves from the swearing-in.
But for many of the Democratic activists who remained in Washington, Mr. Trump’s inauguration was a time to ratchet up public protest and dissent against his presidency.
On a day that is traditionally a celebration of national unity that transcends party politics, Democrats are taking battle stations for what they expect to be a yearslong effort to oppose the new commander in chief.
“We want to stand firm in the face of injustice, and we want to let Donald Trump and our entire federal government know, as well as state governments, that we are determined to see things changed,” said Lauren Footman, 25, a community organizer who is staging an afternoon Rally for Humanity at the Martin Luther King Jr. Memorial to resist what she called the “forces of intolerance.”
“This is about saying to the top leadership of this country, ‘We are watching you, we are ready for the next four years and we’re gearing up to take action,’” Ms. Footman said.
On the campus of George Washington University, a few blocks from the White House, a group of activists planned an eight-hour “resistance training workshop” designed to teach liberal millennials techniques to thwart Mr. Trump, by lobbying Congress, making media appearances or running for office.
“There’s so much energy, and people are in the streets protesting, but we want to ricochet that energy back out into the states so that young people have the skills they need to resist the Trump agenda and get results,” said Maggie Thompson, the executive director of Generation Progress Action, a progressive group focusing on millennials.
The American Civil Liberties Union announced on Thursday that it had filed its first legal action against Mr. Trump, a Freedom of Information Act request for documents about his potential conflicts of interest, and it released a seven-point plan to challenge every aspect of the incoming president’s agenda.
“It’s a first shot across the bow to underscore the fact that no one, not even the president, is above the law, and that there are serious concerns about the president’s disregard for existing laws and statutes,” said Anthony Romero, the executive director of the organization, which is adding 100 staff members — a 10 percent increase — in anticipation of taking legal action against Mr. Trump. “We need to go on offense from the very beginning, and we will litigate everything that we possibly can, we will try to deny them momentum, we’ll try to rob them of time and bandwidth.”
More than 65 Democrats in the House of Representatives — one-third of the caucus — have publicly announced they are boycotting the inaugural festivities on Friday, breaking with custom in a reflection of their alarm about Mr. Trump’s assumption of power.
“I just was overwhelmed by the sense of degradation he’s brought to the office already, with his sordid behavior and damaging words,” said Representative Gerald E. Connolly, Democrat of Virginia. “I cannot lend by my presence any inferential support for what this man has done.”
Representative Gwen Moore, Democrat of Wisconsin, said that for her, attendance at the ceremony would be its own form of protest against Mr. Trump. “When he sees me,” she said, “I want him to see the resistance.”
Mr. Trump’s inauguration is not the first to draw protesters from around the country and opposition from ideological foes, or even to prompt some lawmakers of the opposing party to stay away. But the level of organized resistance to his presidency — by elected leaders, political operatives, activists, lawyers and others — is striking.
Mr. Trump’s approval ratings are exceptionally low for an incoming president, and they are driven by historically low levels of approval from Democrats, said Carroll Doherty, the director of political research at Pew Research Center. His data show that only 13 percent of Democrats gave Mr. Trump positive marks this month for his transition, and 10 percent approved of his cabinet selections. In contrast, 46 percent of Republicans approved of President Obama and his cabinet choices on the eve of his inauguration in 2009.
“You see this extraordinarily low rating by the party out of power,” Mr. Doherty said. Even after a bruising legal battle over the result of the 2000 election, he added, 29 percent of Democrats approved of George W. Bush’s transition — more than double the percentage that approve of Mr. Trump’s.
“These deeply polarized numbers that we saw during the campaign have persisted through the transition, and that is unusual,” Mr. Doherty said.
Ron Klain, who led Al Gore’s legal battle after the 2000 contest, said that he recalled Mr. Bush’s inauguration as “depressing,” but that it did not yield the kind of opposition efforts that Mr. Trump’s has.
“I was not hosting protesters on Inauguration Day 2001,” said Mr. Klain, who is hosting a dinner on Saturday for 25 young people who plan to participate in the Women’s March and other demonstrations this weekend.
Mr. Klain is spending Friday at a conference of Democratic donors and operatives at Turnberry Isle in Aventura, Fla., speaking around the time that Mr. Trump is delivering his inaugural address.
With an opening session entitled “What the Hell Just Happened?” and a panel called “The Road to Fascism?” the three-day gathering was organized by David Brock, a Hillary Clinton-aligned Democratic pugilist, and was expected to draw party luminaries including Mayor Rahm Emanuel of Chicago, the strategist James Carville and Jennifer Granholm, the former Michigan governor.
Mr. Klain, though, planned a quick return to Washington to join his band of protesters. “I’m not going to let Donald Trump chase me out of Washington,” he said.
But for Jennifer Palmieri, a former Obama administration official who served as communications director for Hillary Clinton’s presidential campaign, Inauguration Day is one to spend far away from the White House. She planned to be in New Orleans on Friday and over the weekend.
“I’m not allowing the swearing-in of Trump to drive me out of my own country,” she said, “but headed somewhere that is not likely to care much about politics.