Military activity is fossil-fuel intensive, yet official country data on military emissions is patchy or non-existent. Now a review of 11 recent academic studies by Scientists for Global Responsibility has found that each additional $100bn of military spending leads to an estimated 32m tonnes of carbon dioxide equivalent (tCO2e) being dumped into the atmosphere. The emissions come from direct sources such as fuel-guzzling combat planes, warships and armored vehicles, as well as indirect emissions from transporting equipment, complex global supply-chains and the effects of war fighting itself. The North Atlantic Treaty Organization is a political and military alliance between 32 European and North American countries. In the wake of Russia’s invasion of Ukraine — and mounting threats by Donald Trump to abandon historic allies — NATO announced plans to increase military spending to 3.5% of gross domestic product (GDP), as part of a broader security spending target of 5% GDP for each member country.