Fossil fuel lobbyists can only dream of the kind of access the green movement has at this year’s U.N. climate conference.

Take, for example, Jennifer Morgan. Until February she was head of Greenpeace International. Now she is Germany’s top climate envoy and has been handed the job of finding agreement between almost 200 countries on the most explosive issue at the COP27 talks: Who pays for the damage caused by climate change?

More and more climate activists are treading this path, from being on the outside making demands to working inside some of the most powerful governments in the world. It’s a shift that affords them unmatched power to shape global affairs and guide the planet to a safer climate. But it comes at the price of moral purity.

Morgan's job switch attracted criticism from environmentalists that view the German government as opponents, said Fridays for Future activist Luisa Neubauer, a youth activist who counts Morgan as a friend and mentor. "People have to sort of change sides and I think we are really hard on them."

But Neubauer sees it as necessary for the movement to achieve its broader goals.

“I think she’s a pioneer," she said. "Just like the fossil fuel industries put people everywhere, we need to put people in powerful positions and then not it take personally when that means they have to say yes to some things that we just don't like.”

Morgan insists the most important things haven't changed. “I am in a different role, but I am working for the exact same goals I have been fighting for my whole life: bringing down emissions, accelerating the global energy transition and more solidarity with the most vulnerable," she told POLITICO.

In Germany, environmentalists have never had more power. But in the face of the energy crisis, Greens co-leaders, Foreign Minister Annalena Baerbock (who is Morgan’s boss) and Vice Chancellor Robert Habeck have had to swallow huge ideological gobstoppers in the form of extending the life of nuclear plants and Chancellor Olaf Scholz’s push for African gas.

Environmentalist and former French minister Nicolas Hulot, who quit Emmanuel Macron's team in 2018 citing an “accumulation of disappointments” on climate policy, serves as a cautionary tale for those who grab the scepter.

The reparations issue that Morgan is steering at COP27, known as loss and damage, exposes how far her public position has had to stretch.

On Tuesday evening, Morgan was huddled with her advisers in a brightly lit tent on the conference grounds. A pack of negotiators from the world’s developing countries were marching toward the room, carrying with them an uncompromising demand for a new fund that would transfer reparations from the rich countries that cause climate change to the poor.

Just one year ago at COP26 in Glasgow, in the height of her Greenpeace pomp, Morgan was standing shoulder to shoulder with Pacific islanders and other extremely vulnerable nations against the wealthy polluters that have caused climate change.

Greenpeace this year is backing the poor countries' call for a new fund. But Morgan's new employers in the German government — along with the EU and U.S. — had resisted creating a reparations fund at these talks, if ever. Late on Thursday, the EU, backed by Berlin, finally did make an offer to vulnerable countries to set up the fund.

It’s “one of the most controversial issues ever,” Morgan told POLITICO. With the talks scheduled to end on Friday, she was straining to find a compromise that would satisfy her country, the countries she once championed single-mindedly, and the holdouts.

Morgan has traded bomb-throwing for bomb-catching. In two interviews and various off-record briefings to the press during COP27, she often checked herself, looking vaguely pained and said: “I don’t think I want to go on the record on that.”

"As an activist, my public voice was all I had to bring about change. This position gives me a different set of tools. My job now is not to demand action from others but to act and achieve results," she said.

This self-censorship in public is the most obvious trade-off she has to make. “When you're an NGO, no one has to listen to anything that you say. But you have a lot more control over what it is you can say,” said Kalee Kreider, a former environmental adviser and spokesperson for Al Gore who met Morgan at COP3, back in 1997. In government, it’s the opposite.

Yet more and more of Morgan’s fellow activists are also making the jump and governments in need of climate expertise are willing employers.

In the lead up to COP27, Morgan was asked by the British government to prepare a key report on climate finance. Her co-author was Canadian Environment Minister Steven Guilbeault, also a former director of Greenpeace.

At a lower level, the U.K. government stacked the unit that worked on COP26 with around 20 staff seconded or hired from green think tanks or NGOs. A senior U.K. official, who was not authorized to speak to the press, said it gave the government access to decades of expertise, connections and — crucially — helped bring the green movement on board.

It’s a calculation that’s changing as some governments get more proactive. When Morgan was unveiled by Baerbock as the “face” of German climate diplomacy, she said the newly elected government was now where she could “make the biggest difference.”

For her part, Baerbock nabbed someone who has long been a player at U.N. climate talks. Even as Greenpeace boss, Morgan was one of the few Westerners with the ear of China’s climate envoy Xie Zhenhua. No matter the job, said Kreider “she's not a person that changes or blows with the wind … a lot of trust and respect comes from that.”

Still, Morgan’s move into power poses a challenge to the activists who count her as a friend. Her public backing for a German-led disaster risk insurance scheme is seen by many green activists as a “tactic” to wriggle away from direct payments to communities that have been devastated by climate change, said Neubauer. That is a charge Baerbock forcefully rejected in Egypt on Thursday, saying the initiative was a "building block."

While the power is needed, finding the right trade-off between ideals and deals will take work. “I think on the other side, we haven't figured out yet how to play this inside-outside game without eventually all compromising way too much,” Neubauer said.