The nation’s flagship conservative think tank is pushing back hard on a new book detailing an internal power struggle at the organization—and blaming its former president and his loyalists for attempting to sow divisions on the right.

The Heritage Foundation’s president, Kay Coles James, drafted a lengthy internal memo on Friday hammering reporting on Heritage in the new book American Carnage, authored by Tim Alberta, the chief political correspondent for Politico Magazine. Alberta’s deeply reported book, which chronicles the evolution of the conservative movement under President Donald Trump, examines a contentious leadership fight at Heritage in 2017 that ended with the ouster of its then-president, former Sen. Jim DeMint (R-SC), and a number of his allies.

In her memo, James accuses her predecessor and his staff at DeMint’s newly formed nonprofit, the Conservative Partnership Institute, of leaking some of the unflattering details about Heritage to Alberta. “You should also know that there’s a personal attack on me,” James wrote, including details “presumably based on [Alberta’s] interview with DeMint or others at CPI.”

CPI executive director Ed Corrigan confirmed that DeMint sat for interviews with Alberta, but denied that he or anyone else at the group said anything negative about Heritage—or that the group was even discussed.

"His interview was to discuss the Tea Party, his tenure in the Senate, and President Trump's record on conservative policies and judges," Corrigan said in an emailed statement. "CPI and all of our staff are focused on uniting the conservative movement, and we are proud to work cooperatively with conservative organizations like the Heritage Foundation and hope to continue this work.”

James insists that Heritage will not be “distracted” by the book’s reporting. But her memo, which exceeds 1,100 words, suggests that Heritage is determined to tamp down on any suggestion that the group has lost some of its edge or influence in the wake of DeMint’s departure, and in an era in which its traditional, Reaganesque conservative agenda occasionally clashes with the Trumpian Republican policy priorities of the moment.

Alberta, based on interviews with current and former Heritage staff, including DeMint, portrays Heritage in the Trump era as less aggressive and ideologically committed. And the book attributes that decline, in part, to James’ leadership.

“Nobody was peddling the narrative of Heritage’s unreliability harder than DeMint himself,” Alberta writes in one passage highlighted in James’ memo. “Having been banished from the think tank, its former president assembled his core team of right-wing agitators to launch [CPI]. They went around town whispering to Heritage donors that the group had lost its nerve; that it was going soft to make nice with the establishment; that James was not a fighter for the movement; that she’s a nice lady known for midday naps more than nighttime raids.”

James took particular exception to that characterization. Her critics, she claimed, are actively attempting to sow division and discord on the right. “Personally, I find it unfortunate to read these nasty, even vengeful, comments from other conservatives,” James wrote. “We are disappointed that other organizations have incited these fractures within the movement.”

The bad blood between Heritage and DeMint persisted after his departure from the group. James claims that CPI tried to undermine Heritage with conservative allies, and to poach its staff and donors. She and DeMint met at CPI’s offices “several months ago” to try to smooth over those divisions.

Alberta’s book, which bills itself as a dispatch from “the front lines of the Republican civil war,” appears to have reopened some of those fissures—and Heritage says it’s prepared to push back hard on attempts to revive DeMint-era criticism of the group’s leadership.

“Our team has a strategy in place to respond to media, donors, and key influencers who might read the book,” James wrote. “As of the date and time of this memo, we have not received any media requests about this book and it has not gained any traction referencing Heritage on social media. But we are prepared if they do.”

In an email circulating James’ memo to senior management, Heritage executive vice president Kim Holmes described the book as “riddled with errors and inaccuracies about Heritage.” Mike Needham, the former head of Heritage Action, the group’s advocacy arm, was not “fired,” James writes. And she insists Heritage did not “invent” the individual mandate concept at the heart of Obamacare. (The book says Heritage previously “championed” the idea,” not that it invented it.)

Alberta declined to comment, saying he’d “let the reporting speak for itself.”

Heritage spokesman Greg Scott emailed a statement responding further to Alberta's reporting on the organization. “At the Heritage Foundation, we deal in facts, get results, and work tirelessly to grow the conservative movement," Scott wrote. “The world-class team at Heritage continues to have significant impact on policy and is driving the public debate on the most important issues facing our nation... And we’re just getting started, as we expand our reach to new audiences with our message of hope and opportunity, and ideas that will build a freer and more prosperous America for future generations.”*

James also focused particular attention on Alberta’s motives and conservative pedigree. “Tim is also a Novak Fellow with The Fund for American Studies who previously worked at National Review,” James wrote. “These connections to conservativism appear to have helped him gain access to sources.”

American Carnage and books like it, James wrote, “are designed to pit conservatives against each other.”

Markay worked at the Heritage Foundation from 2011 to 2013.