Does the European Union ‘Rule the World’? Competition Law Diffusion to Singapore and Hong Kong

ABSTRACT This article examines why Singapore and Hong Kong adopted competition law by testing four diffusion mechanisms: coercion, competition, learning, and the Brussels Effect. Using structured process tracing and extensive archival evidence, it evaluates the distinct observable implications of each mechanism. Singapore—often cited as a most‐likely case for the Brussels Effect—adopted competition law only when the United States made it a requirement of the USSFTA. Hong Kong, despite its greater exposure to EU competition enforcement, resisted reform for nearly 15 years and shifted only when Beijing signaled support for a general competition law. In both jurisdictions, firms did not internalize EU standards or lobby for EU‐style rules, and neither regime adopted EU‐type merger control. Competitive interdependence receives no empirical support, while learning operates mainly as an adaptive tool once external pressure is present. The findings refine the scope conditions of market‐driven regulatory diffusion and highlight the political foundations of ‘economic constitutions.’