Despite recent setbacks in the nation’s sustainability efforts, including expected budget cuts to scientific research and environmental programs, the withdrawal from the Paris climate agreement, and a proposal to scrap the Clean Power Plan, the tone of the opening plenary talks at this year’s Greenbuild International Conference and Expo was hopeful.

“We have to be vigilant [about sustainability], even when the world today is a cowardly place,” said Mahesh Ramanujam, the president and CEO of the USGBC, on Thursday evening at the Boston Convention Center.

Although the current federal administration has in many ways turned back the dial on combating climate change, Ramanujam emphasized that local governments can help to counter these regressive shifts in national policy by striving to become LEED certified cities, as Cambridge and Boston are.

Speaking to a packed audience of architects and designers, people in the construction industry, and product manufacturer representatives, Ramanujam also discussed the important role of individuals within the industry to propel sustainability and public health initiatives. He cited Italian architect Stefano Boeri, who champions urban vertical forests, and Doneice Sandoval, founder of Lava Mae, a program that designs mobile showers for homeless people, as examples.

Following Ramanujam was Rick Fedrizzi, the founding chair of the USGBC and the current CEO of the International WELL Building Institute (IWBI). Fedrizzi discussed the Council’s efforts to build an orphanage, designed by HOK, in Port-au-Prince, Haiti, with the Clinton Global Initiative (CGI). The building, officially named the William Jefferson Clinton Children’s Center, is aiming for LEED Platinum certification, and is expected to be a model of green and resilient building practices.

The talks were closed by Bill Clinton, who expanded on Ramanujam’s plea to come together in the face of adversity. “We live in an interdependent world,” said the 42nd president of the U.S. “The most important thing, believe it or not, is not conquering climate change, or solving North Korea, or figuring out how to turn the tide on cyber terrorism—not even removing income inequality and economic immobility from America’s landscape—things I have devoted a lifetime to. The most important thing is how we think. Because how we think will determine whether together, we can do the right thing.”

He took the opportunity to address the anti-evidence sentiment of the Trump administration, citing facts such as: “The murder rate among Muslims in America is about one-third that of the native born; the crime rate among all immigrants, including undocumented immigrants, is one half that of the native born; the small business formation of all immigrants, however, is twice that of the native born,” he said. “This is inconvenient to the narrative,  but it’s true.”

Using these statistics, Clinton leveraged the idea that “people are too focused on what makes us different,” and called upon the audience to embrace diversity, and come together to “change the future.”

“I think that the way the USGBC works is very important not just in conquering climate change, but in preserving the very democracy of our country,” he said. “This is a problem we can fix.”