Elly Pepper of the Natural Resources Defense Council reacted with glee, and confusion, when President Trump tweeted Friday that he would halt a new rule proposed by his administration to allow hunters to import “trophy” elephants killed in Zimbabwe.

Pepper, deputy director of wildlife trade for one of the nation’s most prominent environmental nonprofit groups, had become accustomed to losing out on major Trump administration policy decisions.

“This is a lesson that public pressure can be effective in some instances with President Trump, but then again, I can think of so many other environmental issues where that hasn't been the case,” Pepper said in an interview with the Washington Examiner. “So I am a little perplexed.”

Pepper and the NRDC promptly sued the Trump administration Monday for the Fish and Wildlife Service's decision to overturn an Obama-era ban on elephant trophy imports from Zimbabwe, which was placed in the Federal Register Friday, before Trump intervened.

“Trump's tweets are great news, but they are not enough when it comes to the fate of a species that is already in crisis,” Pepper said, explaining the rationale behind the lawsuit filed in federal court with the Center for Biological Diversity. “Tweets lack legal authority. We want something more permanent.”

Pepper and others who have played primary advocacy roles in the debate over trophy elephants are grappling with how Trump arrived at the decision to override the decision allowing the imports, and what it means.

A White House aide, and others following the issue, say Trump did not know about the administration’s decision to lift the trophy ban until he saw news reports, which were mostly critical of the move.

The criticism came from unlikely places, including conservative media personalities Laura Ingraham, Mike Cernovich, and Michael Savage.

Prominent Republican politicians such as House Foreign Affairs Committee Chairman Ed Royce, R-Calif., and South Carolina Gov. Henry McMaster, also reacted negatively to ending the ban, with Royce pointing out on Friday the military's coup in Zimbabwe just three days before.

“Today Zimbabwe is in economic and political crisis. American citizens in the country are advised to go outdoors only when necessary. In this moment of turmoil, I have zero confidence that the regime – which for years has promoted corruption at the highest levels – is properly managing and regulating conservation programs. Furthermore, I am not convinced that elephant populations in the area warrant over-concentration measures," he said. “The administration should withdraw this decision until Zimbabwe stabilizes."

Environmental and animal rights groups concede those reactions from conservatives, more than their own, likely informed Trump’s decision.

But it’s a mistake to say the backlash from allies alone forced Trump’s hand, said Wayne Pacelle, president of the Humane Society of America.

Pacelle, whose organization lobbied for the ban on elephant imports imposed by the Obama administration in 2014, noted that Trump has acted decisively in other areas, unafraid of backlash.

“The public abhors trophy hunting of elephants, and the president has a lot of intuition and feel for where the American electorate is on issues,” Pacelle told the Washington Examiner in an interview. “You have a very strong and decisive leader in Trump. People have criticized him for that, or lauded him for that. But he is not afraid to take a stand on issues.”

Pacelle was on Capitol Hill last Thursday with Lara Trump, the president’s daughter-in-law and an animal rights advocate, meeting with a half-dozen Republican lawmakers pushing for passage of unrelated animal welfare bills.

The day before, the Fish and Wildlife Service announced it would end the 2014 government ban on trophy hunting in Zimbabwe.

So a conversation with lawmakers that was supposed to be focused on strengthening the federal law against dog fighting and cockfighting, among other issues, naturally turned to elephants.

“It was just pure coincidence that the day before the meeting this news broke, and we at Humane Society reacted to the news and did our best to communicate it to lawmakers,” Pacelle said.

Pacelle said Lara Trump brought up the elephant issue to lawmakers during the Thursday meeting, although he would not say how her views were received nor whether they proved decisive in persuading participants.

“Lara is a broad-minded animal welfare advocate,” Pacelle said. “I didn't really need to check with her on how she views the issue. I know she is not in favor of trophy hunting of elephants. No animal advocate is.”

Yet the Trump administration faced competing impulses from other interests.

White House press secretary Sarah Sanders and other administration officials say the Fish and Wildlife’s decision authorizing elephant trophy imports resulted from a review conducted by career officials started in the Obama administration.

But critics note that both of Trump’s sons, Donald Jr. and Eric, are avid hunters, as is Interior Secretary Ryan Zinke.

The Fish and Wildlife Service, in justifying the decision, announced Friday that killing elephants in Zimbabwe on or after Jan. 21, 2016, and on or before Dec. 31, 2018, "will enhance the survival of the African elephant," according to the notice published in the Federal Register.

African elephants are considered threatened under the Endangered Species Act.

While elephant trophies from other countries with large elephant herds are allowed, Zimbabwe has been a special case for years.

The Obama administration had determined the country's conservation practices were not strong enough for the U.S. to allow trophy imports from there. The Obama Interior Department placed a suspension on trophy exports from Zimbabwe in 2014 and 2015.

Under U.S. law, the remains of African elephant can be imported only if federal officials have determined that hunting them benefits the species. The fees paid to hunt the elephants are supposed to go into conservation programs.

“It's a difference at least in part in wanting to preserve every single animal in the wild versus conserving the species and population as a whole into the future,” said Doug Burdin, senior litigation counsel of Safari Club International, a large group boasting 50,000 members worldwide that supports importing elephant trophies from Zimbabwe.

Safari Club International and the National Rifle Association sued the Obama administration for its 2014 ban, in a case still pending.

Burdin, in an interview with the Washington Examiner, says his group provided information to the Fish and Wildlife Service for its 2017 decision on how to treat elephant imports, and he insists the interactions were with career officials.

But Burdin acknowledged the group hoped Trump administration officials, and people close to the president, would be more sympathetic to their views. He said he’s surprised Trump is angling to block his own administration from lifting the ban.

“Obviously we hoped the Trump administration would take a new look at these issues and be a bit more supportive of hunting, and recognize the benefits to conservation that it brings,” Burdin said. “So the president's action was surprising to us. We didn't expect it, and we didn’t expect the tweets to be so negative. We don't know where it will come out in the end. We are trying to provide him with information so he makes a decision based on the facts and science and nothing else.”

Indeed, neither side of the elephant debate is interpreting Trump’s tweets as official policy and are continuing to make their cases.

Paul Babaz, president of Safari Club International, sent a letter to Trump Monday. The organization issued a “call to arms” to its members last weekend against “hysterical anti-hunters and news media outlets” that “went into overdrive, attacking everyone in sight, including the Trump administration, SCI and even the National Rifle Association of America.”

Pepper said questions persist about whether the Trump administration can take down its Federal Register notice allowing the imports, and if Fish and Wildlife will issue a new rule.

As of Thursday, the Federal Register notice remained.

Tanya Sanerib, a senior attorney at the Center for Biological Diversity, suggested that Trump and his administration likely will make their final decision based on natural impulse, more than anything else.

“There's something about elephants that really does speak to people in a way that perhaps other wildlife and animal issues don't,” Sanerib said. “You have an animal that is not only spectacularly gorgeous, but we know has higher-level thinking and self-awareness, exists in family units, and has a lot in common with humans. We have an ability to empathize with elephants that doesn't always translate to other animals.”