It became known as Rick Perry’s “oops” moment: Standing on stage at a Republican presidential debate in 2011, the then-Texas governor couldn’t recall the third government agency he wanted to eliminate. Perry named the Departments of Commerce and Education, but forgot the Department of Energy, which he clarified later in the debate. Now, he may lead the agency he once wanted to scrap.

On Wednesday, President-elect Donald Trump formally announced his intention to nominate Perry to serve as secretary of energy. “My administration is going to make sure we take advantage of our huge natural resource deposits to make America energy independent and create vast new wealth for our nation, and Rick Perry is going to do an amazing job as the leader of that process,” Trump said in a statement. Perry called the news “a tremendous honor,” and added that he looks forward to “promoting an American energy policy that creates jobs and puts America first.”

Perry won’t necessarily be pursuing his own energy agenda if confirmed by the Senate. He will be tasked with carrying out the president-elect’s policy aims. Trump aide Sean Spicer emphasized that point during a call with reporters on Tuesday when asked whether Trump feels comfortable with Perry’s earlier call to eliminate the agency. Trump is looking for people “to implement his agenda,” Spicer insisted, “It’s his agenda that’s being implemented, not somebody else’s.”

That won't be enough, however, to re-assure critics of the nomination, and there are already indications that Democrats in the Senate will pushback. Martin Heinrich, a Democrat from New Mexico who sits on the Energy and Natural Resources Committee which will consider the nomination, called Perry “utterly unqualified to lead this critical agency,” in a statement on Tuesday. “President-elect Trump has signaled his blatant hostility to the Department,” he added, “by nominating someone who has proposed eliminating this entire agency.”

The Energy Department oversees a wide array of priorities. It maintains the nation’s arsenal of nuclear weapons, and runs national laboratories that conduct scientific and energy technology research, including research and development focused on renewable energy. The national laboratories play a critical role in driving U.S. scientific innovation. The department is also responsible for environmental cleanup efforts, sets energy efficiency standards, and grants authorizations for natural gas exports.

The approach presidential administrations have taken in the past to managing the agency, as well as the apparent priorities of the Trump transition team, offer insight into what might change at the department. As Brad Plumer points out at Vox:  

The nuclear weapons and environmental cleanup programs tend to remain fixed from administration to administration. But the energy programs have changed significantly with each new president. …  [Under Obama] the Department of Energy has greatly expanded a variety of clean energy programs — the stimulus bill of 2009 created massive loan guarantee programs for solar, battery, and electric car companies.

[…]Donald Trump’s transition team, for its part, has generally signaled that it wants to tilt the Energy Department’s focus away from renewables and back toward programs that support oil and gas drilling (and possibly nuclear power).

It’s possible that Trump’s hostility toward President Obama’s climate agenda may also impact the agency. Trump has called climate change a “hoax” and campaigned on promises to dismantle Obama’s climate initiatives. The transition team recently asked the Energy Department to provide names of employees who have attended United Nations climate talks and identify programs “essential to meeting the goals of President Obama’s Climate Action Plan.” The department rejected the request to identify individuals by name, but that won’t quell fears among environmentalists, Democrats, science advocates, and agency employees. An anonymously-quoted former department staffer told Politico the request seemed like a “witch hunt.”

If Perry becomes energy secretary, his background in conservative politics will mark a dramatic break with the scientific expertise of the current Energy Secretary Ernest Moniz, a nuclear physicist. Perry has a track record of questioning climate science. “The science is not settled on this,” he said during a presidential debate in 2011, an assertion that misrepresents the overwhelming scientific evidence that human activity is driving global warming.

This has alarmed some science advocates. “The Energy Department is a massive science agency that plays a major role in scientific enterprise at the federal level. It’s not always the case that it’s been led by a scientist, but to have somebody dismissing climate science as the head of the department, that’s worrying,” said Andrew Rosenberg, the director of the Center for Science and Democracy at the Union of Concerned Scientists, a science advocacy organization.

There are other notable differences between the outgoing and potentially incoming cabinet secretaries as well. Moniz played a major role in the negotiation of the Iran nuclear deal, an international agreement that Perry has claimed “jeopardizes the safety and security of the free world.” Perry has also been sharply critical of the Obama administration’s energy policy overall, accusing the president of “waging a war on coal,” and “creating obstacles to onshore and offshore oil and gas production.”

As Texas governor, Perry presided over an uptick of natural gas drilling and defended oil drilling in the Gulf of Mexico after the 2010 Deepwater Horizon spill. A New York Times report on his record as governor from 2011 noted that “Under Mr. Perry, Texas has moved eagerly to build coal-fired power plants, even as other states have stopped issuing permits for the plants because of pollution concerns.” But Perry has supported the wind industry in Texas as well, signing legislation that mandated an expansion of renewable energy capacity.

Perry tried and failed to win the Republican nomination for president in 2012, and launched another unsuccessful presidential bid in 2016. Earlier this year, he became a contestant on the television show Dancing with the Stars only to be eliminated not long after it began. Perry is also a member of the board of directors for Energy Transfer Partners, a company that owns Dakota Access LLC, which is attempting to build the Dakota Access Pipeline.

Perry is the latest in a series of Trump cabinet picks who have been critical of the agency they may lead or advocate an agenda at odds with the agency’s mission under President Obama. Scott Pruitt, the Oklahoma attorney general who Trump has chosen to head the Environmental Protection Agency, has been a high-profile legal opponent of the agency’s efforts to regulate greenhouse gas emissions. Andrew Puzder, Trump’s choice for labor secretary, has criticized worker protections undertaken by the Labor Department under the Obama administration.

Perry has not always agreed with Trump, or even supported him. Last year, he denounced him as a “cancer on conservatism,” calling Trumpism “a toxic mix of demagoguery, mean-spiritedness and nonsense that will lead the Republican Party to perdition if pursued.” But that anti-Trump conviction appears to have been short-lived. Earlier this year, Perry endorsed Trump, saying that while “he is not a perfect man” he believes that Trump “loves this country and he will surround himself with capable, experienced people.” Now, one of those people Trump surrounds himself may be Perry himself.

Given Trump’s track record of punishing what he perceives to be disloyalty it might seem surprising that he would want Perry to serve as his energy secretary. Perry’s about-face, however, seems to have satisfied the president-elect. “We’re big fans of Governor Perry, someone who did a fantastic job with the state of Texas,” Trump aide Jason Miller told reporters on Tuesday.