I look at it like this, if China were poised to attack us, we would max out resources to defend ourselves and survive the attack. We wouldn't worry about budgets or debt or the deficit. We would put the entire country to work making tanks and planes and bombs and soldiers.
Climate change is that threat.
In addition to that, there's a school of thought that budgets don't have to be balanced and deficits don't matter. We control our currency.
From the same Vox piece:
The US government can spend all the money it wants. What ultimately sets the limits on America’s ability to invest are its resources. It has so much labor potential, so much natural resources, so much manufacturing capacity, etc. By paying for stuff, injecting money into the economy, the government puts those resources to work.
If the economy overheats, one or more of those resources nears its limits, scarcity drives prices up and inflation ensues. To stop short of that, the government can pull some money out, by scaling back programs or raising taxes. Taxes are simply a way of extracting money from the economy.
Stony Brook University professor Stephanie Kelton (a Modern Monetary Theory guru, Sanders adviser, and likely GND adviser in some capacity, at some point) calls it an economy’s natural speed limit. As long as the economy stays under that limit and avoids inflation, the government can spend more money. A deficit isn’t a bad thing, it’s just a foot on the accelerator.