The shutdown might be over for now, but President Donald Trump’s threat to declare a national emergency still looms. The continuing resolution passed Friday afternoon does not contain funding for a border wall, and the president has suggested that if Congress doesn’t compromise on a funding plan within three weeks, he may still proclaim a national emergency at the border. When Trump first threatened to use emergency powers to unlock $5.7 billion for his $20 billion border wall project, Sen. Marco Rubio, R-Fla. came out strongly against it — but not for humanitarian reasons or because he is concerned about an unmistakable creep toward authoritarianism. Rather, Rubio worried that normalizing the call for a state of emergency might make it easier for politicians to act on a genuine existential threat: “If today, the national emergency is border security,” said Rubio, “tomorrow, the national emergency might be climate change.” Rubio is right to worry. Climate change is a legitimate emergency, unlike Trump’s border “crisis,” which is a fabrication sewn of foam-mouthed racism and vain partisan panic. Security and militarization at the border has increased steadily over the last decades; border crossings have been in decline for years; and most heroin smuggled over the border comes through legal border crossings, not the areas that are targeted for a wall. Meanwhile, overwhelming scientific evidence says that climate change could take hundreds of millions of lives and trigger a global economic collapse in the next several decades, making anything we might recognize as human civilization physically impossible. It’s not as if migration and climate are unrelated, either: Climate change is poised to cause the largest mass migration in human history, as millions are forced to leave homes rendered uninhabitable by rising sea levels, unbearable heat, and declining crop yields. Trump’s border and immigration policies, in other words, are climate policies, and efforts to restrict access to temperate parts of the world will be a defining political issue of the next century. In addition to being justified, declaring a national emergency on climate change wouldn’t be all that novel. As Jeffrey Toobin pointed out in the New Yorker, the National Emergencies Act has been invoked 41 times since it was passed in 1976, and there are 31 emergencies currently in effect. What constitutes an emergency has never been clearly defined, and most of those currently in place allow the White House to place sanctions and restrictions on countries whose policies it disagrees with, such as regulating vessels that might enter Cuban waters or mobilizing the military as George W. Bush did in the days after 9/11. Concerns about the expansion of executive authority are well-placed, but meeting the climate change goals recommended by the Intergovernmental Panel on Climate Change requires a level of mobilization that our balkanized, partisan government may be ill-equipped to handle. After all, decarbonization isn’t just about building a symbolic infrastructure project. It would involve transitioning every sector of the economy off fossil fuels at lightning speed. The sheer amount of administrative collaboration involved — across government agencies, industry, and civil society — is staggering, and would require massive levels of government investment and going toe-to-toe with one of the world’s most powerful industries.

Rep. Alexandria Ocasio-Cortez, D-N.Y., recently called the threat of climate change “our World War II.”

Because of the effort and exigency involved, climate scientists are urging a “wartime footing” to decarbonize the economy over the next 16 years. They’re increasingly joined by politicians like Rep. Alexandria Ocasio-Cortez, D-N.Y., who recently called the threat of climate change “our World War II” at a recent Martin Luther King Jr. Day event. If climate change is our World War II, why shouldn’t our politicians should act like it? As it became increasingly likely that the U.S. would enter World War II, Franklin Roosevelt and his advisers were eager to build up the country’s manufacturing capacity. But after years of feeling threatened by New Deal reforms, executives weren’t keen to have the state tell them what to do. Congress was also hesitant to appropriate more money to defense and have the state play a stronger role in directing industrial activity, mindful of public pushback to similar measures that were enacted during World War I. But the cause of winning the war — an “unlimited” national emergency, as Roosevelt called it right before U.S. entry — was considered too important to be derailed by corporate executives or political squabbling. Declaring a limited national emergency in 1939 allowed the White House to begin its Protective Mobilization Plan, shifting resources to Britain’s Royal Navy, expanding military ranks, and building out industrial capacity to produce things like military aircrafts. Once Roosevelt declared a full national emergency after Pearl Harbor, federal agencies’ role in the economy was able to greatly expand. The government could now control prices and wages while directing industry leaders to meet manufacturing needs. Firms that refused to go along with government orders faced a federal takeover. By 1945, around a quarter of all U.S. manufacturing had been nationalized. No doubt, this is the kind of outcome that terrifies Rubio. But without it, it’s not clear that the war effort would have been successful. And the pending battle against climate change is one that none of us can afford to lose. There are serious risks to expanding executive authority. While Roosevelt’s war mobilization was ultimately critical to defeating Axis powers and ending the Depression, it also gave him the authority to intern over 100,000 Japanese-Americans, and wars abroad have reliably been an excuse to suppress civil liberties at home. Because of these risks, and because leveraging the National Emergency Act sidesteps our democratic processes, it should be treated as a nuclear option. Such tools exist to intervene where our democratic processes fail. That said, there’s reason to suspect they already have.