WASHINGTON — The bad blood started early.
In 2008, Neera Tanden, then a top aide on Hillary Clinton’s first presidential campaign, accompanied Mrs. Clinton to what was expected to be an easy interview at the Center for American Progress, the influential group founded by top Clinton aides. But Faiz Shakir, the chief editor of the think tank’s ThinkProgress website, asked Mrs. Clinton a question about the Iraq war, an issue dogging her candidacy because she had supported it.
Ms. Tanden responded by circling back to Mr. Shakir after the interview and, according to a person in the room, punching him in the chest.
“I didn’t slug him, I pushed him,” a still angry Ms. Tanden corrected in a recent interview.
Ms. Tanden now leads the Center for American Progress, Mr. Shakir runs Bernie Sanders’s presidential campaign and the enmity between the two camps burst into the open last weekend. Mr. Sanders, angry about a video produced by ThinkProgress that ridicules his new status as one of the millionaires he has vilified on the campaign trail, sent a scorching letter to the center’s board, accusing Ms. Tanden of “maligning my staff and supporters and belittling progressive ideas.”
The blowup is another reflection of the ideological divisions among Democrats, this time between a legacy Clinton organization and a liberal wing trying to move the party to the left to harness the energy of millennials. Mr. Sanders’s team remains convinced that the Democratic establishment worked behind the scenes to deprive him of the party’s nomination in 2016; his campaign has cast the group as beholden to corporate interests set on thwarting him in 2020.
Ms. Tanden rejected that characterization and asserted in an email to Mr. Shakir that the center shares “the goals of unity.” Jodi Enda, the editor in chief of ThinkProgress, said that her website is editorially independent and that “we don’t have a favored candidate, and we don’t have a candidate who we disfavor.”
Still, Ms. Tanden’s mother, Maya Tanden, says that her daughter “can be very aggressive.”
“She’s not going to let anyone rule over her,” she said, “and she has loyalty to Hillary because Hillary is the one who made her.”
“Those Bernie brothers are attacking her all the time, but she lets them have it, too,” Maya Tanden said. “She says Sanders got a pass” in 2016, “but he’s not getting a pass this time.”
The Center for American Progress and its sister political arm, with a $60 million combined annual budget and 320 staff members, have played an outsize role in the Democratic Party for nearly two decades. Founded in 2003 by top advisers to Bill and Hillary Clinton, the organization has sought to rebrand itself as a brain trust for the anti-Trump resistance.
Its donor rolls overlap substantially with those of the Clintons’ campaigns and foundation. The think tank has taken in millions from interests often criticized by liberals, including Wall Street financiers, big banks, Silicon Valley titans, foreign governments, defense contractors and the health care industry. Individual donors can ask to remain anonymous.
Money to the Center for American Progress from the personal foundation of the Facebook creator Mark Zuckerberg surged to $665,000 in 2018 from $15,000 in 2017, while Facebook fended off scrutiny for mishandling users’ personal data, fueling violence and providing a platform for Russian election interference.
Last year, the center got $1 million from the family foundation of Jonathan Lavine, a managing partner at Bain Capital, and at least $1 million from the tech industry’s Silicon Valley Community Foundation. It also received $225,000 from the private foundation of a Walmart heir, Sam Walton.
Ms. Tanden, whose salary was $397,000 in 2018, was an unpaid adviser to Mrs. Clinton’s 2016 campaign while running the think tank, and was considered a candidate for a top White House job had Mrs. Clinton won the presidency. Ms. Tanden says she has founded six new policy-intensive groups as the center’s president and increased its annual budget by 25 percent.
“That’s what she does — she shows up at rich people’s places because she needs funds from them,” Ms. Tanden’s mother said. “That place runs on Neera Tanden.”
Tom Daschle, a lobbyist and former South Dakota senator who is the chairman of the Center for American Progress’s board, said he has full confidence in Ms. Tanden, who he said brings credibility, stature and “enormous experience both managerially and around the issues.” He added that “there are people that are not as supportive of Neera’s leadership, and that’s natural.”
From 2016 through last year, the center accepted nearly $2.5 million from the United Arab Emirates to fund its National Security and International Policy initiative, according to previously unreported internal budget documents. From the start, the decision to solicit money from the United Arab Emirates, an ally of Saudi Arabia with a problematic human rights record, fanned internal dissent. A Center for American Progress spokeswoman said on Monday night that it had decided in December to stop taking money from the country.
Tensions boiled over in October, after the Saudi-born Washington Post journalist Jamal Khashoggi was killed and dismembered at the order of Crown Prince Mohammed bin Salman of Saudi Arabia, according to an assessment by the C.I.A. Before the C.I.A.’s conclusion became public — but while the crown prince was widely suspected of ordering the killing — the center had pursued plans for a joint panel on “the U.S.-Saudi relationship in light of recent events,” and had invited the Saudi ambassador to the United States, Prince Khalid bin Salman, the crown prince’s brother, according to an internal email to executives.
But the Saudi ambassador fled the country and the plan dissolved. Internal criticism of the Emirati donations leaked into the news media, prompting an in-house investigation that led to the firing of two staff members. One of them, Ken Gude, a longtime executive, is working with a lawyer on a wrongful dismissal lawsuit.
In November 2015, after Ms. Tanden invited Prime Minister Benjamin Netanyahu of Israel to a question-and-answer session at the center, a dozen staff members stood during an all-staff meeting and read a statement of protest. “Our goal is to promote humanity and shut down oppression and genocide and terrorism. Bringing in another head of state with a record of oppression would further push our mission away,” it read in part.
In an email Ms. Tanden sent on the day of the Netanyahu visit, stolen and released by WikiLeaks, she told the think tank’s founder, John D. Podesta that the “far left hates me” for hosting Mr. Netanyahu, but the invitation “may have sealed the deal with a new board member.” Ms. Tanden was wooing Mr. Lavine, a pro-Israel philanthropist.
The next month, Ms. Tanden wrote a jubilant email to Mr. Podesta, telling him Mr. Lavine was joining the board. “So Netanyahu was worth it,” she added, with a smiley face emoji. Mr. Lavine no longer sits on the center’s board, but his foundation remains a big donor.
“The Netanyahu event was arranged with the public and private support of the Obama administration, and the notion that it was done at the behest of any donor is preposterous,” a center spokeswoman said.
“It’s difficult as a think tank to know exactly how to handle things” like the Netanyahu pressure, said Judd Legum, who was the founding editor of ThinkProgress. “You don’t want to only have people come in who agree with you,” he said, but “there were people who felt it wasn’t tough enough on Netanyahu, and I understood where they’re coming from.”
Few rival Ms. Tanden for her bellicosity on Twitter. She has told James Zogby, a pro-Sanders pollster, that “an army will rise up against this bs”; threatened Starbucks’ chief executive, Howard Schultz, with a boycott if he runs for president; and traded insults for two years with Jill Stein, the 2016 Green Party presidential candidate viewed by Ms. Tanden as a spoiler.
One recent night, Ms. Tanden feuded on Twitter with liberals over whether Mrs. Clinton condemned far-right hatemongers strongly enough more than two years ago. The online bickering raged for an hour, drawing trolls from both factions, when the woman originally targeted by Ms. Tanden’s tweets delivered a wake-up call: “neera, you’re responding to a graduate student on Twitter at 1:40 am.”
Ms. Tanden, who rallied weeping staff members after Mrs. Clinton’s loss, has expertise on domestic policy that dates to the early 1990s. As an Obama administration official, she worked to pass the Affordable Care Act, and during the Trump administration, she has called the center to the ramparts during Republicans’ efforts to repeal it.
Under Ms. Tanden’s leadership, the center started a lobbying and social media campaign to save the health care act, including building a web portal that relayed the stories of nearly 3,000 people whose coverage was in danger. Now, as many Democratic presidential candidates drift left toward “Medicare for all” plans like Mr. Sanders’s, the Center for American Progress is pushing its own plan, which reserves a role for private insurance companies, unlike the Sanders proposal.
Last week, the center held an off-record briefing and made follow-up contacts with reporters, picking apart the details of Mr. Sanders’s plan. In a fund-raising email to supporters on Sunday night, Mr. Sanders said the briefing was an effort by the think tank “to stop Medicare for All and our progressive agenda.”
Mr. Legum said that “from the beginning, the problem was there are all these little factions on the left, each caring about their own issues and their own agenda — and CAP was supposed to be a big umbrella.”
Now, he added, “We’re in another period where there’s new energy, new perspectives and people who are once again skeptical of CAP.”
Ms. Tanden acknowledged tensions with what she called “millennial agitators” in her party, but blamed Mr. Trump, who made “crazy, radical ideas seem more normal,” she said in the interview.
Maya Tanden, Ms. Tanden’s mother, said her daughter was “sick of” the nonstop fund-raising and political squabbling. “She said, ‘Another two years and I’m gone, I don’t care what I do,’” Maya Tanden said.
Neera Tanden said she has no such plans.
“When Trump won, I was one of the better prepared people to deal with his victory. I righted this ship to be an effective response to him,” she said. “A place to come up with the ideas that would formulate the next generation of ideas.”