For many centuries, conquest was commonplace, and its attractiveness was central to the character of international politics. Why has it declined? Existing theories cannot explain why powerful countries no longer conquer states with easily extractable wealth. We develop an explanation based on the relationship between a potential conqueror's economic productivity and its ability to profit from conquest. Productivity has opposing effects on conquest's profitability: it raises the opportunity cost of each asset diverted to conquest, but also reduces the quantity of assets required for conquest. The net effect is determined by the composition of investment in innovation. We document that since at least 1950 investment has been predominantly aimed at civilian, not military innovations, so that rising productivity should reduce conquest's net profitability. Using cost analyses of comparable wars, we estimate bounds on the profitability of conquering the oil and gas reserves of the Persian Gulf, a very tempting target, for the United States and Iraq, two potential conquerors of widely differing productivity. Though both mechanisms operate, we find that the net effect of higher productivity is to reduce the profits from conquest. Moreover, this net effect is large enough to render conquest generally unprofitable for contemporary high-productivity states.

International organizations (IOs) increasingly pool resources and expertise. Under what conditions do they pool rather than compete when their activities overlap? Drawing on elite interviews, I argue that even though many cooperation decisions are made by staff possessing high degrees of autonomy from member state principals, IOs are more likely to pool resources when their leading stakeholders are geopolitically aligned. Regardless of whether member states directly oversee the negotiation of these arrangements, staff design policies that are amenable to major stakeholders. I test this argument with regression analysis of an original data set that documents patterns of co-financing and information sharing among IOs in the development issue area. I further supplement these tests with an elite survey experiment deployed via LinkedIn to bureaucrats from various development IOs. Across the board, I find evidence consistent with my theory.

Scholars and practitioners continue to debate transatlantic burden sharing, which has implications for broader questions of collective action and international organizations. Little research, however, has analyzed domestic and institutional drivers of burden-sharing behavior; even less has disaggregated defense spending to measure burden sharing more precisely. This paper enhances understanding of the relationship between national political economies and burden shifting, operationalizing burden shifting as the extent to which a country limits or decreases defense expenditures, while at the same time favoring personnel over equipment modernization and readiness in the composition of defense budgets. Why do countries choose to allocate defense resources to personnel, rather than equipment modernization? I find that governments slightly decrease top-line defense spending in response to unemployment while shifting much more substantial amounts within defense budgets from equipment expenditures into personnel. This research highlights the intimate connection between Europe’s economic fortunes, transatlantic security, and burden sharing in North Atlantic Treaty Organization and the European Union – of particular interest as a pandemic buffets the transatlantic economy. It also points policy analysts toward factors more amenable to political decisions than the structural variables generally associated with burden sharing, bridging significant gaps between defense economics, security studies, and comparative political economy.