Democracies are often thought to provide more public investments than non-democracies, as citizens can demand these services at the ballot box. Yet many scholars recognize that autocracies also engage in distributive programs, and electoral incentives can encourage targeted public investments within democracies. A growing concern across contemporary democracies is their declining ability to deliver complex public projects, especially relative to autocracies, potentially straining the social contract. Understanding these dynamics requires analyzing how political systems interact with variation in public goods’ unit costs, design, implementation, and material characteristics.