Ideally, the next few decades will see all the world’s economies begin the difficult transition towards carbon neutrality, so as to stop anthropogenic climate change. Fossil fuels will represent a progressively smaller share of what drives vehicles and power plants, and complimentary measures will enhance carbon sinks.
If all that happens in the civilian sphere, is there any chance we will see it in the military? Military vehicles are definitely fuel hogs: whether it is supersonic fighter jets or main battle tanks driven by gas turbines.
It seems plausible that armies will be the last hold-out, when it comes to achieving carbon neutrality. National security has almost always been given priority over civilian needs, especially in non-democratic states. Furthermore, if weapons that produce large amounts of greenhouse gases are more effective than those that do not, any state with current or possible future enemies will find their military strategists unwilling to abandon them. It is also plausible that climate change itself will produce a more dangerous world, in which politicians and the public are even more supportive of developing military strength than they are now.
Perhaps the armed forces are such a small share of total emissions that this isn’t really a problem. Indeed, it does seem plausible that we can cut down the level of emissions to the point where the risk of climate change is much diminished, without having to tinker with them at all. Still, the question of how to move to a carbon-neutral world entirely unthreatened by climate change will eventually involve the question of how to get generals to give up their carbon-intensive habits, perhaps after titans of business and ordinary citizens have eventually done so.