Will 2019 be remembered as the year in which climate change denial was defeated? The global climate strike, Greta Thunberg’s meteoric rise to international prominence, as well as several high-profile international conferences and reports – all contributed in putting climate skeptics on the back foot.

Even Donald Trump, who previously claimed that the climate crisis was a “hoax” invented by China to hold back American industry, has recently begun to brag about all his administration has done to address it. Following suit, the rest of his party is scrambling to develop a coherent environmental platform, more in line with their electoral base’s shifting views.

But the next steps in the global fight against the climate crisis remain far from clear. In the speech she delivered to US Congress in September, Thunberg maintained: “No matter how political the background to this crisis may be, we must not allow it to become a partisan political question. The climate and ecological crisis is beyond party politics. And our main enemy right now is not our political opponents. Our main enemy is physics.”

While Thunberg’s intention was evidently to preserve the environmental movement’s unity and common resolve, this may paradoxically soon start to look like a new form of climate denial. As the issue rises to the top of everyone’s agenda, several difficult questions which were previously kept in the background – or indeed actively suppressed – by the environmental movement are becoming impossible to ignore.

The environmental movement is going to have to become more, not less, politicized, to keep up the momentum

For one, no one seems quite clear what is the ultimate goal of the global fight against the climate crisis. Is it merely to enable constant economic growth in a sustainable way, or is it about imposing limits on humanity’s ambitions, in pursuit of a more harmonious relationship with nature?

Even assuming that question can be settled, it remains to be determined what is the relationship – and whether there are any tradeoffs – between environmentalism’s overarching goal(s) and other potentially desirable ends, such as personal freedom, distributive justice and respect for established traditions and ways of life.

Then there is the issue of means. Whether humanity chooses to fight the climate crisis through centralized, state-based efforts, decentralized market mechanisms, or individual and community-level changes in lifestyle has profound political and distributional consequences. So, it matters what decisions are made in this respect.

Finally, even the relevant temporal horizon remains open to disagreement. Should we care about what happens in 10,000 years? A few generations? Or the immediate 20 years?

Far from having straightforward answers, all these questions are inherently political, since they point to deep conflicts in values and interests. They delineate the contours of a new “politics of environmentalism” that is beginning to take shape as climate change rises to the top of humanity’s present concerns.

We already see this new politics taking shape in emergent debates over competing proposals for addressing the climate crisis. Bernie Sanders’ and Alexandria Ocasio Cortez’s respective versions of the Green New Deal are very different from the proposal for a European Green Deal recently put forward by the new president of the European commission, Ursula von der Leyen.

The first approach wants to connect the issue of the climate crisis with social justice, and advocates for a massive expansion in the role of the state to manage the transition to renewable energy. The second approach treats the issue of the climate crisis in isolation from other social and political issues, and proposes market rather than state mechanisms to address it.

Nor are these the only two options on the table. Another prominent strand of contemporary environmentalism is the one heralded by Pope Francis in the 2015 encyclical letter Laudato Si, which folds the struggle against the climate crisis into a broader critique of the “modern myth of unlimited material progress” on the basis of a religiously inspired conception of the inherent rights of the “natural order”.

While this chimes with radical ecology’s longstanding commitment to the idea of “de-growth”, it is also compatible with classical conservatism’s critique of modernity, which has traditionally stigmatized the hubris in humanity’s dream of complete domination over nature. Several ideas contained in the pope’s encyclical have in fact been taken up by more conservatively minded political and religious organizations, in an attempt to give greater resonance to the conceptual affinity between political conservatism and natural conservation.

Even some strands of the nativist far right have begun to develop their own brand of environmentalism. The French Rassemblement National’s leader, Marine Le Pen, has sought to connect the problem of environmental degradation with her party’s broader opposition to globalization and immigration. This translates into a form of “green nationalism” focused on the protection of local cultures, products and traditions.

This growing diversification of environmental positions is a sign that the movement as a whole is maturing. Environmentalists of all stripes are realizing that there remain important political decisions to be made even after climate crisis denial has been defeated.

These decisions cannot be taken by purely technical or scientific means. On the contrary, the fact that the environmental movement has so far remained the preserve of a small technocratic elite has done more to invite populist backlashes than to further its own goals.

It is a good thing that all the available options are now being laid bare, in order to better assess their relative merits in an open and democratic way. Whether we like it or not, the environmental movement is going to have to become more, not less, politicized, to keep up the momentum it has acquired so far.