In the months since he published his papal appeal for global action to fight climate change, Pope Francis has advanced beyond measure the public dialogue on the central environmental challenge of our time. In schools, churches, and community groups everywhere, his encyclical, Laudato Si, On Care for Our Common Home, has fired the collective conscience of the nation.

This week, the pope lends voice to urgency when he journeys to Washington, D.C., to deliver his message of moral imperative to President Obama and Congress before traveling to New York to make his case before the United Nations General Assembly.

We have a moral obligation to future generations, to safeguard their natural inheritance, set an example of care, and leave them a livable planet.

When the pontiff and the president sit down at the White House on Wednesday, it will be a meeting of largely kindred souls. No leader anywhere has done more than Obama to cut the dangerous fossil-fuel pollution that’s driving global climate change. The president is far from satisfied, though — nor should he be. “We’ve got to move faster,” he said earlier this month at a school in Kotzebue, Alaska. “We’re not moving fast enough.”
Pope Francis will face the main reason for that the next day, when he delivers remarks to a joint meeting of the House and Senate on Capitol Hill, bringing a message of moral clarity to a place of moral ambiguity.