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The U.S. president, referring to "a problem unprecedented in our history" and "the greatest challenge our country will face during our lifetime," warned "we must not be selfish or timid if we hope to have a decent world for our children and grandchildren."

Just before presenting his proposals to Congress, he added that "further delay can affect our strength and power as a nation" and that this issue will "test the character of the American people and the ability of the president and the Congress to govern.

"This difficult effort," he added dramatically, "will be the moral equivalent of war."

The president was Jimmy Carter in 1977, not Joe Biden this week. And the issue was the energy crisis — not climate change. But Biden could replicate Carter's rhetoric today. Only instead of the moral equivalent of war, Biden should urge world leaders to avoid war caused by climate change.

That threat was starkly stated in a torrent of reports from the departments of Defense, Homeland Security and the Treasury, as well as the Office of the Director of National Intelligence, issued before Biden embarked to Rome for the G-20 Summit and Glasgow for the U.N. Climate Change Conference.

"Climate change is reshaping the geostrategic, operational, and tactical environments with significant implications for U.S. national security and defense," the Pentagon reported. "Increasing temperatures; changing precipitation patterns; and more frequent, intense, and unpredictable extreme weather conditions caused by climate change are exacerbating existing risks and creating new security challenges for U.S. interests."

The intelligence report projected risk assessment through 2040 and predicted "high" chances in eight of 15 specific risks (notably no risks were considered "low"). Some of them were categorized as "geopolitical tensions over climate responses," including the perception of insufficient contribution to reduce emissions, demands from developing countries for financing and technology assistance, resistance from petrostates to transition from fossil fuels to clean energy, and competition with China over key minerals and clean energy technology.

Two risks intoned instabilities within countries: a strain on energy and food systems, and a greater demand for aid and humanitarian relief. And two considered "climate-exacerbated geopolitical flashpoints," including cross-border water tension as well as conflict and cross-border migration attributed to climate change.

"Climate change will increasingly exacerbate risks to U.S. national security interests as the physical impacts increase and geopolitical tensions mount about how to respond to the challenge," the report read.

"It's real," Robert Blecher, program director at the International Crisis Group's Future of Conflict Program, told me when asked about the confluence of conflict and climate change. "There is an increasing body of research that demonstrates this conclusively," he added, mentioning South Sudan and Nigeria as just two examples.

The White House sees it, too. "Extreme weather events and conflict are the top-two drivers of forced displacement globally, together responsible for the annual movement of nearly 30 million people from their homes," it said in a migration report. "There is a strong correlation between countries and regions most vulnerable to climate change and those that are fragile and/or experiencing conflict or violence."

There also can be a strong correlation between migration, whatever its causes, and the rise of right-wing political responses.

"Anybody who has looked at how migration has affected politics in Europe sees that," said Blecher, citing Brexit and other illiberal responses to the Mediterranean migration crisis. "And so even people who have more generous impulses in terms of welcoming people in need are quite aware of the negative political consequences that can happen." So the climate crisis can amplify the crises seen in migration and democracy worldwide, which makes success in Glasgow that much more important.

"If people are forced to migrate to another part of the country or to a completely different country altogether, that's really driven by necessity," said Ama Francis, climate displacement project strategist at the International Refugee Assistant Project. "What we do now to cut carbon pollution makes a really important difference to their ability to stay at home."

Cutting carbon emissions was the focus of environmental scientists well before political scientists. "There are a bunch of environmental scientists, myself included, who are working on climate change and the consequences from water availability to endangered-species protection that have thought of that as being in the environmental domain," said Jessica Hellmann, director of the University of Minnesota's Institute on the Environment.

But beyond that, Hellman said, "there are two other worlds that have always been paying attention to climate change: One is insurance companies, and the other the military."

Concern among insurance companies reflects a broader economic threat, and the Treasury Department's Financial Stability Oversight Council is paying attention. For the first time, Treasury Secretary Janet Yellen said last week, the FSOC is "recognizing that climate change is an emerging and increasing threat to U.S. financial stability." Calling it a "unique, existential risk for the planet," Yellen said that "It does not require a vivid imagination to see how climate change could threaten the financial system."

A threat to the financial system is also a threat to national security, and like complex ecosystems themselves, the threat to them from climate change is interrelated, too.

"We may have started this dialogue about climate change, about concerns of planetary health," Hellmann said. "But increasingly, we realize that climate change intersects with and is critically important to everything we care about: food security, international political stability, environmental justice, public health, as well as environmental quality."

Accordingly, failure to rise to the climate-change challenge threatens everything we care about. Including the most precious resource: life, which is threatened both by environmental catastrophe and the corresponding conflicts the recent reports warn about.

Carter, like Biden, wasn't known for soaring oratory, and his address didn't really rally Congress or the country. But his energy crisis rhetoric resonates today.

Especially the words Carter added after evoking the moral equivalent of war.

"Except," he said, "that we will be uniting our efforts to build and not to destroy."