Update: On December 19, the Heritage Foundation named Kay Coles James as its new president. Our explainer on the tumult at the conservative think tank, from May of this year, is below.

Original story: In the latest seismic shake-up of a major conservative institution during the age of Trump, the Heritage Foundation announced on May 2 that it had ousted Jim DeMint, the former senator who has led the right-wing think tank since 2013. Ed Feulner, who had served as Heritage’s president for most of the foundation’s existence until retiring in 2013, will step in as president again until a permanent successor is named.

Thomas Saunders III, an investment banker who chairs Heritage’s board of trustees, released a statement blaming “significant and worsening management issues” at Heritage on DeMint “and a handful of his closest advisers,” which led the board to unanimously vote to ask for DeMint’s resignation (though one board member resigned in protest before the vote).

For his part, DeMint fired back, calling the move “puzzling” due to the board’s past praise of his work and its approval of bonuses for his management team.

While it may be tempting to ascribe DeMint’s downfall to ideological tensions or Trump-related controversies, the true explanation seems to lie in office politics.

Several anonymously sourced media accounts around the time of the announcement described a personality clash and turf war between DeMint and Michael Needham, the 35-year-old head of Heritage Action, the foundation’s political arm. It’s a relationship that has gotten so tense that Needham once reportedly threw a chair across the room in anger.

The strange thing about this conflict is that both DeMint and Needham have reputations for being ideological bomb throwers who want to shake up Washington and aren’t afraid to go after the Republican Party establishment in order to do so — that is, they seem to agree on a whole lot.

But the two apparently could not effectively work together. Needham’s allies (and now the Heritage board) put the blame for this on DeMint for what they say is poor management, while DeMint’s defenders have argued that Needham has been ambitiously trying to usurp a leading rival to aggrandize his own position.

Whatever the case, the turmoil at Heritage raises further questions about just what the influential organization’s role will be at a time when Republicans control both the presidency and Congress.

The Heritage Foundation was founded to be an explicitly political conservative think tank

Founded back in 1973 after conservative Capitol Hill aides and wealthy donors concluded that existing Washington think tanks were either too liberal or too ineffective at influencing legislation, the Heritage Foundation exists to advance conservative ideas — which it has generally defined as a hawkish foreign policy, cuts to taxes and government, defenses of traditional and Christian religious values, and in recent years opposition to immigration reform — into law and government policy.

Nowadays, it’s become a behemoth — according to its 2015 financial disclosures, it raised about $90 million that year and had 572 employees. Much of this cash comes from extremely wealthy conservatives, but over decades Heritage has built up a significant small-donor base as well.

Importantly, Heritage has always been more oriented around political activism than the average think tank. Back in 1985, a New York Times article reported: “Heritage analysts are not expected to develop highly original ideas in major books or articles that will shape scholarly thinking on an issue. Rather, they are expected to cultivate sources in Congress and the Administration, sense what issues are becoming ripe and produce terse position papers that can be used to sway political argument.”

The Times story went on to quote Heritage’s executive vice president Phillip Truluck as saying, ''We don't sit around smoking pipes and thinking deep thoughts about what the economy will look like five years from now.”

That strategy paid off for the foundation after Ronald Reagan won the presidency in 1980. Heritage helped supply the new conservative administration with both staff and policy proposals — “Mandate for Leadership,” a book thousands of pages long that contained Heritage policy proposals, became inspiration for incoming Reagan officials looking for conservative ideas.

“In think tank world, the perception of power is also a source of power,” says Dan Drezner, author of The Ideas Industry, a book on think tanks. “So when it became clear Heritage was the favored think tank of the Reagan administration, that enhances its own influence.”

And indeed, Heritage continued to be influential on the right in future decades, particularly in crafting welfare reform legislation in the mid-1990s. A Heritage analyst even famously proposed an early version of what eventually became the individual mandate in Obamacare. (When he suggested it, it was intended as a conservative alternative to President Bill Clinton’s health reform proposal.)

Though Heritage has certainly employed some respected scholars who have done good work, its reputation overall is much more controversial. It is clearly trying to advance a political agenda and has even more of a reputation for slanting its analysis with that in mind than other ideological think tanks do. (Take, for instance, absurdly optimistic estimates of how Paul Ryan’s budget will affect the economy.) Suffice to say, many liberals and centrists don’t tend to view Heritage very highly, but it’s nevertheless amassed significant influence on the right of the political spectrum.

The turning point for Heritage wasn’t DeMint’s appointment — it was Michael Needham’s

Though Heritage has always been political, a sea change for the group occurred at the height of the Tea Party movement in 2010, when its leaders and board decided for the first time to launch a political advocacy arm called Heritage Action for America. It would be run by Michael Needham, the then-28-year-old protégé of longtime Heritage president Ed Feulner.

As Needham later explained in an interview with Vox’s Ezra Klein, there was a perception at Heritage that “our business model was not working.” Despite unified Republican control of Washington during the Bush years, “the conservative agenda wasn’t advancing” — because, Needham said, “the people who were being listened to were the lobbyists.”

The answer, then, would be “to go outside to mobilize people.” Rather than simply writing studies or evaluating proposed legislation, the purpose of Heritage Action would be to pressure members of Congress — through, for instance, mobilizing conservative constituents across the country and funding attack ads against politicians. “As Ronald Reagan said, ‘If you can't make them see the light, make them feel the heat,’” Feulner and Needham wrote in an op-ed. Heritage Action, they continued, “will provide the political heat.”

An excellent 2013 New Republic profile of Needham by Julia Ioffe describes what happened next:

[Heritage Action’s leaders] designed a brutally effective way to activate Heritage’s base of almost 700,000 donors, as well as to harness the diffuse Tea Party fervor across the country. In nearly every congressional district, they recruited Heritage Action “sentinels,” usually ordinary citizens with a surplus of time and enthusiasm, who were trained, outfitted with information kits, and asked to recruit and organize the local faithful. When Needham sounded the alarm, the sentinels and their infantries flooded the offices of their representatives with vitriol.

And crucially, after the GOP retook the House of Representatives in the 2010 midterms, Heritage Action decided to aim a great deal of that heat at Republicans who were backing policies they deemed insufficiently conservative. This would make Heritage as a whole immensely controversial on the Hill, as Republicans who viewed themselves as staunch conservatives came to think they were being held to an impossible standard of purity.

Then Jim DeMint escalated Heritage’s turn toward confrontation

This newly aggressive approach at Heritage Action predated DeMint’s tenure as president of the main Heritage Foundation. But when he was announced for that job in late 2012, it seemed clear that Heritage’s board and donors were looking for something similar for the organization as a whole.

As many observed at the time, DeMint had no reputation for scholarship or for immersing himself in the details of policy wonkery. In the Senate, he was known for being a right-wing bomb thrower willing to upset his party's leadership by supporting conservative primary challengers to mainstream Republicans. “I’d rather have 30 Marco Rubios than 60 Arlen Specters [in the Senate],” he said (referring to the moderate Republican senator who in 2009 flipped to become a Democrat).

DeMint’s mission in life was, it appeared, to force Washington to the right through aggressive political rhetoric and pressure. Accordingly, grassroots conservatives who distrusted party leadership viewed DeMint as one of the few men of principle in the Senate.

So as President Obama’s second term began in 2013, DeMint and Needham worked in tandem to pressure congressional Republicans not to compromise — on immigration reform, on the farm bill, and then — fatefully — on passing a government funding bill that included money for Obamacare. As Ioffe wrote:

Heritage Action organized DeMint’s nine-city tour, and Needham blitzed the conservative media—giving constituents the impression that defunding Obamacare in one knockout move was perfectly plausible. ... Washington conservatives can barely contain their anger at Needham for his ideological inflexibility and aggressive, zero-sum tactics.

An unpopular two-week government shutdown ensued, and after Republicans were roundly blamed for it, they caved and funded Obamacare. Needham and DeMint were now major movers for a PR disaster for the Republican Party that was widely viewed as a strategic blunder that resulted in no policy gains. Heritage Action had less sway in the next round of funding fights — then-Speaker John Boehner said that outside groups like them had “lost all credibility” — and a Politico magazine profile asked whether DeMint had become “the most hated man in Washington.”

But when Trump unexpectedly won the presidency last November, DeMint had savvily decided not to position Heritage against Trump despite the GOP nominee’s lack of fealty to traditional conservatism. And once Trump had to staff up an administration, his people were as hungry for policy ideas and appointee suggestions as Reagan once was — and they looked to Heritage. Reports of the Trump transition team considering major budget cuts based off Heritage proposals soon circulated. Heritage, it appeared, was on top once again.

But behind the scenes, DeMint and Needham’s relationship soured

Publicly, DeMint and Needham appeared to be on the same page. Both, for instance, sharply criticized the March version of Speaker Paul Ryan’s American Health Care Act for not repealing enough of Obamacare, with DeMint writing that the bill needed a major overhaul and Needham writing: “It is an awful bill that will impact millions of Americans’ lives and is opposed by nearly every serious conservative health care analyst. This legislation is a policy, process, and political disaster.”

But many reports in media outlets tell the story of a behind the scenes turf war and conflict between the two men.

The Federalist’s Mollie Hemingway’s sources claim that DeMint had actually been trying to rein in Needham because the latter was making too many enemies on Capitol Hill. She writes:

Multiple sources told The Federalist that Needham bristled at DeMint’s repeated attempts to assert control over the splinter organization and began plotting to overthrow DeMint once it became clear that the former South Carolina senator had no desire to outsource control of the think tank to the 30-something political operative with no policy background.

The Daily Beast’s Lachlan Markay and Asawin Suebsaeng corroborate this somewhat, writing:

On March 28, just four days after Republicans pulled the plug on the first incarnation of Trumpcare, Heritage held a conference call for its members to discuss the bill and the diminished Obamacare-repeal prospects. Heritage Action had actively campaigned against the original Trumpcare bill as at best a capitulation to the progressive premises of President Obama’s signature legislative victory. According to a Heritage member who was on the call and took notes, DeMint and Needham were both chairing the conference call—and their stark differences were on full display. DeMint was busy trying to calm down the callers who were angered that Heritage’s advocacy arm helped sink Trump’s first real Obamacare-repeal push. Needham, alternatively, was aggressively defensive of Heritage Action’s campaign to kill the effort, and emphasized that it was the right course of action.

Meanwhile, Needham’s allies have been claiming that DeMint is a poor manager and that his focus on politics made him “incapable of renewing the foundation's place as an intellectual wellspring of the conservative movement,” as Politico’s Eliana Johnson and Nancy Cook reported. (Their piece is where the chair throwing comes in.)

DeMint, who at one point suggested he would retire this year, announced at a senior management meeting several months ago that he intended to extend his contract. Even at that point, his relationship with Needham had become so strained that the news caused Needham to throw a chair across the room after DeMint left, according to a Heritage staffer.

The Washington Examiner’s Philip Wegmann quotes a source claiming that what Needham truly wanted was to “reorder” Heritage so that “the Heritage Foundation manufactures good policy and Heritage Action fights to get those ideas implemented into law.” And he quotes another source claiming Needham has been "trying to take over Heritage forever" and likely wanted to use Feulner as a “proxy to control the place."

Whatever the case, the denouement was ugly. Politico broke the news that DeMint was being pushed out, which triggered dueling leaks from the warring camps over the ensuing days. After Heritage’s board finally met to officially oust DeMint in May, their statement announcing their decision was notably nasty as far as things like these go.