BRITTANY HOSEA-SMALL / AFP / GETTY

The federal government spends roughly $700 billion a year on the military. It spends perhaps $15 billion a year trying to understand and stop climate change.

I thought about those numbers a lot last week, as I tried to stop my toddler from playing in ash, tried to calm down my dogs as they paced and panted in mid-morning dusk light, tried to figure out whether my air purifier was actually protecting my lungs, tried to understand why the sky was pumpkin-colored, and tried not to think about the carcinogen risk of breathing in wildfire smoke, week after week.

The government has committed to defending us and our allies against foreign enemies. Yet when it comes to the single biggest existential threat we collectively face—the one that threatens to make much of the planet uninhabitable, starve millions, and incite violent conflicts around the world—it has chosen to do near-nothing. Worse than that, the federal government continues to subsidize and promote fossil fuels, and with them the destruction of our planetary home. Climate hell is here. We cannot stand it. And we cannot afford it either.

Again and again, Republicans have insisted that it is clean energy and a safer, stabler homeland that we cannot possibly afford. “The Paris climate accord is simply the latest example of Washington entering into an agreement that disadvantages the United States to the exclusive benefit of other countries, leaving American workers, who I love, and taxpayers to absorb the cost in terms of lost jobs, lower wages, shuttered factories, and vastly diminished economic production,” Donald Trump said, pulling out of the agreement, citing its “draconian financial and economic burdens.”

But the Intergovernmental Panel on Climate Change estimates that global warming of 1.5 degrees Celsius above preindustrial levels would cause something like $50 trillion in economic damage by the end of the century. The warmer the planet gets, the more expensive the consequences, and some scientists now predict that if the global community fails to act, temperatures will rise 4 degrees Celsius by 2100. If we do not limit emissions, economic activity across 22 vital American business sectors could decline by half a trillion dollars on an annual basis, one study found. No country save for India is expected to bear a heavier financial burden from climate change than the United States. (India’s anticipated damage is so high because of its already hot climate and large GDP.)

A warming planet is destroying the country’s physical infrastructure: In 2019 alone, the United States experienced more than a dozen billion-dollar weather events, and 2020 might be worse. Fires in California and Oregon are incinerating homes, businesses, schools, power lines, and roads. Hurricanes in the Gulf Coast are swamping mobile homes and carrying away cars and livestock. The United States faces the potential task of relocating towns and cities and fortifying others, trapped in an endless cycle of destruction and rebuilding.

Climate change is damaging American productivity too, sapping away output from millions of workers and thousands of businesses. Researchers have estimated that every workday above 86 degrees Fahrenheit costs a given county $20 per person in lost income, with other studies showing workers who toil outside, such as construction workers and farmers, facing the worst and harshest effects. Temperature increases screw with the economy’s “basic elements, such as workers and crops,” the researchers Tatyana Deryugina and Solomon M. Hsiang argue.

Climate change is killing Americans. Wildfires, heat waves, mudslides, hurricanes, and floods lead to hundreds if not thousands of deaths every year. But those are only the direct fatalities. Climate change is increasing rates of conditions such as heatstroke. Climate change is worsening birth outcomes, leading to more premature deliveries and maternal deaths. Climate change is putting the world at risk of famine, and the United States at risk of hunger.

The air we are breathing is toxic because of our addiction to fossil fuels. As Dave Roberts writes at Vox, ditching gas would be worth it for the effects on air pollution alone. The researcher Drew Shindell of Duke University has testified that keeping the world to a 2-degrees-Celsius pathway would prevent 4.5 million premature deaths, 3.5 million hospitalizations and emergency-room visits, and 300 million lost workdays over the next 50 years.

Climate change is also increasing rates of domestic abuse, pumping up the number of gun deaths, leading to more violent interactions with police officers, inciting resource conflicts, and raising the likelihood of war and civil conflicts. We all are at greater risk of violent death because of climate change, and not just as a result of changes in the weather. Trump sees himself as the law-and-order candidate, the man who can restore peace and security to the country. But homes across the West Coast are burning down. Some of my fellow Californians were recently immolated. My unhoused neighbors are suffering from smoke-induced asthma in the middle of a respiratory pandemic.

The Paris Agreement, the Green New Deal, cap-and-trade legislation, renewable-energy mandates: These things are not expensive. They are cheap compared with the cost of climate change. And they are necessary investments in our collective security, no less important or vital than investments in our military. Instead of subsidizing fossil fuels, the government could be creating millions of green jobs that would save the lives of millions around the planet. This election, and every election from here on out, is existential on this issue: If 2016, per the conservative writer Michael Anton, was the Flight 93 election, 2020 is the 4-degrees-Celsius election. Politicians can choose the safer, greener path for all of us, or the path to oblivion.

What price would we put on breathing without fear? What price would we put on keeping our children safe? What price would we put on being freed of this terror?

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