The climate crisis and the justice of wars

<p dir="ltr">In an age of deepening climate crisis and insecurity, the “carbon costs” of preparing for and fighting wars are gaining public attention. Greenhouse gas emissions from wars in Ukraine and Gaza are being counted in almost real-time and reported by journalists around the world. Such work highlights the significant ways that wars exacerbate the global warming that is putting billions of lives around the world at ever greater risk. It also provokes the following questions: in an age of deepening climate crisis and insecurity, under what circumstances, is war morally justifiable? How does climate change affect the ways wars ought to be fought? And how does climate change impact the creation of a just and lasting peace? To answer these questions, we examine how the core principles of the just war theory/tradition ought to be interpreted in an age of climate crisis. We conclude that while the climate crisis does not render war morally impermissible, many of the principles constituting jus ad bellum, jus in bello and the jus post bellum require at least some reinterpretation. This, we argue, points to the moral imperative of military decarbonisation and grand strategies of restraint regarding the use of military force.