A mood of pessimism already shrouds the upcoming United Nations climate summit in Glasgow, where world leaders, including U.S. President Joe Biden, will try to agree to next steps in the urgent fight against global warming. These summits often don’t live up to their expectations, even as the stakes for their success or failure grow ever higher. It seems unlikely that Glasgow will produce the major commitments experts say are necessary to keep temperatures from rising above dangerous thresholds and to help protect vulnerable communities from the worst impacts of the changing climate.

Before Biden arrives in Glasgow, however, he will make a visit that might help lift some of the gloom. The president meets Pope Francis on October 29 in the Vatican. As a devout Catholic, Biden has personal reasons to look forward to the meeting. But the president and his Catholic-heavy entourage are also eager to access the pope’s status as a global influencer: Francis leads the only world religion recognized as sovereign under international law, and the Holy See has some diplomatic clout and influence within the United Nations’ family of organizations. The White House hopes that the Vatican can amplify Biden’s most aspirational goals, especially around climate change.

Climate change is the matter of greatest urgency to the pope and the president because they both see it as a fundamental threat to civilization. The United States proved to be an ambivalent actor when the Trump administration retreated from the commitments of the 2015 Paris climate accord, but now Biden hopes to partner with a pope whose moral authority is broadly admired. And this pragmatic pontiff is happy to be used. 

To achieve the goals of climate agreements such as the Paris accord, countries must make innumerable technological and policy adjustments. But political and economic elites have often proved unwilling to drive these changes, a failure that has rankled the pope. A Biden-Francis partnership would galvanize more people—mobilized by religious leaders—to care and to act, putting greater pressure on argumentative bureaucrats and self-interested politicians. Francis is one of the few world leaders who can help push action on climate change beyond the paralysis of politics.


Global warming is the subject of the pope’s most radical encyclical, Laudato si, issued in 2015 to influence the summit that produced the Paris climate accord. The encyclical added a spiritual dimension to the issue, explicitly linking poverty, peacemaking, and social justice to environmental concerns and compelling activism from people of faith. Francis’s eloquent treatise grounded the church’s earlier rhetoric on the environment in science and theology. Biden, who was vice president when the encyclical was released, referred to the papal document as an inspiration.

The Biden administration and the Vatican have been laying the groundwork for this meeting for months. Special Presidential Climate Envoy John Kerry, who is Catholic, met Francis in May in Rome. Secretary of State Antony Blinken, whose wife is Catholic, appeared at the Apostolic Palace in June for extensive consultations. Speaker of the House Nancy Pelosi, also Catholic, brought her husband to see Francis in October. Each meeting involved conversations about action on climate change.

The pope can help push action on climate change beyond the paralysis of politics.

The pope’s team and many of the figures in the Biden administration have worked together before. When the Obama administration reached an impasse in its secret talks with Cuba in 2014, then Secretary of State Kerry made his first trip to the Vatican and probed its willingness to get involved. Just two months later, the president explored the subject with Francis himself. By directly engaging with Cuban President Raul Castro via the Cuban cardinal Jaime Ortega, then by serving as neutral mediators for final negotiations, Francis and his lead diplomat, Secretary of State Cardinal Pietro Parolin, facilitated an ambitious agreement between the United States and Cuba in December 2014. The pope served as a sort of diplomatic guarantor in the negotiations between the two countries, which deeply mistrusted each other.  

The working relationship between the Vatican and the White House can be harnessed to good effect in the fight against climate change. The United States needs a trusted partner with no material interests and minimal bureaucracy (unlike the UN) to encourage other countries to take serious action—and to also pressure U.S. politicians. (Senator Joe Manchin, Democrat of West Virginia and another Catholic, has so far refused to agree to key climate change provisions in proposed infrastructure legislation.) Such a practical collaboration between pontiff and president has happened before, when Pope John Paul II and his diplomats worked with the White House in the 1980s to navigate the potentially chaotic decline and fall of communism.

One of the weaknesses of the Paris accord is that it has no enforcement mechanism and relies on countries to meet their own self-assigned emission-reduction targets. The church can play a real role in holding countries accountable. Its representatives and institutions around the world can place serious pressure on governments that are dragging their feet, as in Brazil, for example. Through direct intervention as well as via national bishops’ conferences, the Vatican can remind recalcitrant politicians of the urgency of fulfilling their climate commitments.

Whether the Holy See can help with China, the single biggest emitter of greenhouse gases, is less clear. Critics—including former U.S. Secretary of State Mike Pompeo—have assailed Francis and Parolin for pursuing good relations with Beijing and for signing a secret 2018 deal, which was renewed in 2020, specifying a joint process for appointing local bishops. The Holy See’s dealings with Beijing don’t give the pope any special leverage over President Xi Jinping’s environmental decision-making. But Francis will surely share his insights about Xi and Beijing with the Americans because he believes hostility between China and the United States endangers the world.     


The church’s work in the “global South” makes it an invaluable partner in broader efforts in support of both adaptation to climate change and its mitigation. Low- and middle-income countries are most likely to experience the worst impacts of climate change, including food insecurity, forced migration, and economic hardship. But there is a marked gap between the level of available scientific research relevant to poor countries and that of research related to the developed world. Catholic educational and charitable institutions are keen to help rectify this knowledge imbalance while supporting efforts to build resilience in countries such as the Catholic-majority Philippines, a nation at great risk to the changing climate, and in Africa, where the church is experiencing its fastest growth.

Indigenous communities in the Amazon and in Asia embody superb examples of sustainable lifestyles that don’t deplete the environment. The church has stepped forward to support indigenous peoples in the defense of forests and lands where they have lived harmoniously—until development and deforestation encroached—and to highlight the abiding value of their knowledge and ways of life. Around the world, the church can point to innumerable ways it has fostered sustainable, environmentally sound reforms, from the readoption of Incan terracing methods that conserve water in Peru to teaching people in Bangladesh how to cleanse toxins from wastewater using duckweed.

The church has even been involved in such projects in the United States. The District of Columbia’s largest solar project was developed by Catholic Charities, the Archdiocese of Washington’s philanthropic arm, which set up over 5,000 solar panels on land adjoining a home for the elderly poor run by Mother Teresa’s religious order. It produces energy, offsets costs at all properties owned by the network, and serves as a model for other organizations looking to boost the use of renewable energy. At this late stage in the climate crisis, the church has the experience at the local level to support programs that help efforts to mitigate climate change and adapt to its damaging consequences.


Francis exerts influence beyond his own church and its institutions. He addressed Laudato si to “every person living on this planet” and evoked other faith traditions in the document. In the encyclical, he called for a renewed commitment from more people and organizations to make up for decades of tentative and faltering progress: “Regrettably, many efforts to seek concrete solutions to the environmental crisis have proved ineffective, not only because of powerful opposition but also because of a more general lack of interest.” 

The pontiff has also mobilized other religious leaders since 2015, when the encyclical was published. On October 4, Francis teamed up with his friends Ecumenical Patriarch Bartholomew of Constantinople, Metropolitan Hilarion of Russia (worth noting: Bartholomew’s and Hilarion’s respective churches are deeply at odds at the moment, but the men still came together for this event), Archbishop of Canterbury Justin Welby, and Sunni Grand Imam Ahmad al-Tayyeb together with Shiite Muslim, Jewish, Hindu, Sikh, Buddhist, Taoist, Zoroastrian, Confucian, and Jain representatives—some 40 religious leaders in all—to sign an appeal directed at the upcoming UN Conference of Parties in Glasgow.

The appeal calls on governments to meet the Paris accord targets of net-zero carbon emissions and a global average temperature increase of 1.5 degrees Celsius. It outlines expectations that wealthy countries step up their own mitigation efforts and at the same time offers greater financial assistance to poorer countries to cope with the negative impacts of rising temperatures and to transition to clean energy, the sustainable use of land, and more ecologically conscious food systems. For their part, the other religious leaders pledged to educate believers on the imperatives of tackling climate change and ensuring that their institutions make green investments. Organized by the Vatican, the day-long meeting was an impressive display of the cross-cultural conviction that, as its concluding text observes, “We have inherited a garden; we must not leave a desert for our children.”


Francis hopes to impress on Biden a more positive vision of American power—one that moves away from an emphasis on militarized solutions. The U.S. military is also directly linked to significant environmental damage: British researchers concluded in 2019 that the U.S. armed forces and their supply chains comprise one of the largest climate polluters in human history. As a believer, Biden should be open to his spiritual adviser’s insights. And as a politician, he knows that Francis has the credibility and the international network to help the United States advance its climate agenda and restore some of its waning global prestige.

Biden bears heavy crosses: a family in which children and grandchildren clearly depend on his emotional strength; a Congress trying his patience; the persistence of COVID-19 and the social conflict it inspires, further fueling political division; and the national humiliation that followed the rapid collapse of the Afghan government after the U.S. withdrawal. Francis will likely tell the president that God rewards those of great forbearance. And, it is hoped, the United States’ light can shine again in Glasgow. 

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