As the world reels from the news yesterday that the U.S. intends to pull out of the global Paris Agreement, there are still reasons to hope that our children can inherit a healthy planet. Paul Hawken, the well-known environmentalist, has a plan. His recent book is called Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming and it does just what the subtitle suggests. Under his coordination, researchers and scientists around the globe spent the last three years modeling what it would take to reduce carbon emissions or sequester carbon from the atmosphere. The book presents 100 proven interventions to immediately begin to stem the tide of climate change.

The good news is that the most effective intervention is not even in the Paris Agreement. Empowering girls and women through a combination of education and family planning is the number one thing the world can do to address climate change, ahead of switching to solar energy, wind energy, or a plant-rich diet. Investing in both girls’ education around the globe and enabling women access to contraception and reproductive healthcare would result in 120 gigatons of carbon reduced by 2050, a staggering amount compared to the 90 gigatons that could be reduced by better management of harmful chemical refrigerants like chlorofluorocarbons (CFCs). Demographers, global development specialists, and education advocates have long known about the connection between girls’ and women’s empowerment and smaller, more sustainable families. Research suggests that the difference in family size for a woman with 0 years of schooling compared to a woman with 12 years of schooling is about four to five children. And several studies have projected slower population growth if all girls around the world receive a secondary school education—as much as two billion fewer people on the planet for 2050 than if current fertility rates persist, and over five billion fewer people by 2100. Indeed, reaching a sustainable population growth rate could be realized even more quickly if the 225 million women around the world who want to avoid pregnancy but do not have access to contraception or control over their reproductive lives were given access to safe and voluntary family planning. The majority of these women live in the world’s 69 poorest countries, and it’s no coincidence that many of these countries are where girls have the hardest time going to school.

While there is reason to hope, it is not clear that girls’ and women’s empowerment will fare any better in U.S. foreign policy. With the president’s reinstatement and expansion of the Mexico City Policy, better known as the Global Gag Rule, preventing any foreign aid or federal funding to organizations providing or promoting abortions; with his vague termination of Let Girls Learn; and with his significant budget cuts proposed to foreign assistance, support for family planning and girls’ education seems sharply at risk. Brookings Senior Fellow George Ingram predicts that in order to reduce the foreign aid budget by one-third, the president would likely start with the “big ticket” items. Global health, the largest assistance category at $8.5 billion, includes large budget programs like PEPFAR—the “program that put the brakes on the global HIV/AIDS pandemic and, last year, provided life-saving treatment to 11.5 million people around the world.” It also includes smaller budget programs like maternal and child health that are not only life-saving, but also “popular with Congress and reflect the best of American values and national interest.”

Perhaps the best strategy is to work outside the U.S. to forge common cause with environmentalists, climate scientists, and women’s rights activists. In a forthcoming report, the Center for Universal Education at Brookings outlines three promising platforms for such cross-sectoral partnership and collaboration between women’s rights, education, and climate actors, including 1) promoting the proven link between girls’ and women’s enhanced reproductive health and rights and smaller, sustainable families, 2) building a pipeline of environmental leadership opportunities for girls, and 3) increasing girls’ and women’s learning opportunities and skills development for a green economy. Important, too, is working with new global actors to make the link between girls’ education and climate change. In a speech yesterday the French President Emanuel Macron extended an invitation to American “scientists, engineers, entrepreneurs, and responsible citizens who were disappointed by the decision of the President of the United States” to come work collaboratively with France to fight climate change. We propose he push France’s climate action further and to champion girls’ education and family planning as an easy win for making the planet great again. After all, he has appointed half his cabinet as women.