The 1990s will demand a redefinition of what constitutes national security. In the 1970s the concept was expanded to include international economics as it became clear that the U.S. economy was no longer the independent force it had once been, but was powerfully affected by economic policies in dozens of other countries. Global developments now suggest the need for another analogous, broadening definition of national security to include resource, environmental and demographic issues.
The assumptions and institutions that have governed international relations in the postwar era are a poor fit with these new realities. Environmental strains that transcend national borders are already beginning to break down the sacred boundaries of national sovereignty, previously rendered porous by the information and communication revolutions and the instantaneous global movement of financial capital. The once sharp dividing line between foreign and domestic policy is blurred, forcing governments to grapple in international forums with issues that were contentious enough in the domestic arena.
Despite the headlines of 1988-the polluted coastlines, the climatic extremes, the accelerating deforestation and flooding that plagued the planet-human society has not arrived at the brink of some absolute limit to its growth. The planet may ultimately be able to accommodate the additional five or six billion people projected to be living here by the year 2100. But it seems unlikely that the world will be able to do so unless the means of production change dramatically. Global economic output has quadrupled since 1950 and it must continue to grow rapidly simply to meet basic human needs, to say nothing of the challenge of lifting billions from poverty. But economic growth as we currently know it requires more energy use, more emissions and wastes, more land converted from its natural state, and more need for the products of natural systems. Whether the planet