This comes as a new study by Brown University finds the U.S. military emits more greenhouse gases each year than many countries, including Sweden and Portugal. The study found that if the Pentagon were a country, its emissions would make it the world’s 55th largest contributor. The study’s author, professor Neta Crawford, said, “Climate change is not a potential risk. It has begun, with real consequences to the United States. Failing to reduce greenhouse gas emissions will make the nightmare scenarios strategists warn against—perhaps even 'climate wars'—more likely.”