Demographic and environmental factors have claimed a dominant position in the post-Cold War security discourse. According to the neo-Malthusian conflict scenario, population pressure on natural renewable resources makes societies more prone to low-intensity civil war. On the contrary, resource-optimists concede that agricultural land scarcity caused by high population density may be a driving factor behind economic development, thus causing peace in a long-term perspective. These notions are tested in a quantitative cross-national time-series study covering the 1950-2000 period. The results do not provide strong support for either perspective. Countries experiencing high rates of population growth, high rates of urbanization, or large refugee populations do not face greater risks of internal armed conflict. There is some indication that scarcity of potential cropland may have a pacifying effect. However, where land scarcity combines with high rates of population growth, the risk of armed conflict increases somewhat. This trend is particularly marked for the 1970s, the decade that saw the great rise in neo-Malthusian concerns. Claims that the world has entered a ‘new age of insecurity’ after the end of the Cold War, where demographic and environmental factors threaten security and state stability, appear to be unfounded. Overall, the robustness of the empirical support for both paradigms is low. A strong emphasis on security as a macro rationale for reducing global population growth thus seems unwarranted.