Photovoltaic modules and a windmill of a wind farm at the village of Feldheim near Berlin. (Michael Sohn/Associated Press)

Jean-Marc Ayrault is France’s minister of foreign affairs and international development.

Climate change is already disrupting the environmental, economic and political balance across the world.

We must face up to this reality. We did this in December 2015, when 195 countries adopted the Paris agreement on climate change — an unprecedented world-level consensus made possible thanks to the commitment of each nation, including the largest greenhouse-gas emitters, and of course the United States, which played a key role in making this remarkable outcome possible.

Since then, 141 parties have ratified the Paris agreement, including the United States, France, the European Union as a whole, China and India, and the agreement entered into force in November 2016. Now is the time to implement it — to actually reduce our greenhouse-gas emissions, to ensure that policies match national commitments. It is time to develop and market clean technologies, and to seize new national and international economic opportunities, which many U.S. companies will be able to do. It is also time to demonstrate solidarity with countries that are in vulnerable situations, have played a lesser role in bringing about climate change and are less well-off but have nevertheless pledged to join the common effort to curb the changes. These major changes are already underway.

The efforts we make today will allow our children and grandchildren’s world to remain livable. These efforts may be considered sacrifices. I prefer to see them as an investment in our future.

And this is also how economic actors around the world perceive the drive to modernize our cities, to transition toward more sustainable energy, to adapt our production technologies in all sectors to our carbon-emission reduction goals and to the constraints of global warming. Policies that lead to a low-carbon economy also lead to enhanced competitiveness and innovation. Opting out of this effort may well satisfy short-term interests in specific sectors, but it would ultimately harm long-term interests. On the contrary, those who invest sooner, including individual companies, will reap the greatest benefits. Such policies also bring social benefits, first and foremost in the field of health, because they contribute to curbing atmospheric pollution while also creating local jobs, for example in renewable energy.

This global fight cannot succeed if all parties are not fully on board and if they don’t assume their share of the burden or seek to capitalize on the opportunities. It is time to call on all stakeholders to mobilize. We are counting on the U.S. presidential administration, on Congress, on states and on cities, as well as on businesses and civil society as a whole, to keep the United States committed, along with the rest of the world, to this ambitious goal.