Military expenditure associated with substantial material intensification of the global economy

This study reveals a strong positive association between the global military expenditure (MILEX) as a share of GDP and lagged material intensity of the global economy. It is estimated that 1% variation in the global MILEX ratio leads 0.2014 kg/USD variation in the material intensity (C.I. 95%: 0.132–0.270 Kg/USD; R ²  = 0.60; p < 0.001) driven primarily by non-biomass components (including metals, non-metallic minerals, and fossils) and insignificant biomass variation. Probable causal pathways are discerned as a combination of direct first-order sectoral effects (MILEX is more material intensive than rest of the economy), second-order structural reinforcement of other material-intensive industries, and lastly, third-order socio-geopolitical effects. Results indicate that global adoption of NATO’s 5% MILEX targets entail a substantial increase in the material intensity, threatening global sustainability, and risking resource-driven conflicts.