International organisations are currently plagued by allegations of powerful states wielding undue influence over outcomes. These include recent revelations about Australia, Japan, Saudi Arabia, and other countries pushing back against the United Nations on climate change, suggestions that senior World Bank officials intervened to boost China’s ranking in the Bank’s Doing Business index, and suspicions that China influenced the World Health Organization’s approach to the Covid-19 pandemic.

Underlying all these controversies is the simple reality that powerful countries exert great influence over m...