Japan has been considered a role-model for the successful pursuit of ‘progress’ or national development in Siam/Thailand since the late 19th century. As this article shows, the Japanese exemplar played a significant role in Siamese/Thai political discourse, with three of the kingdom’s most important conservative thinkers – King Vajiravudh, Luang Wichit Wathakan, and Mom Ratchawong Kukrit Pramoj – writing in detail about Japanese history and interpreting Japanese battlefield and economic successes as the outcome of the national character of the Japanese. In contrast, the role of political institutions and institutional change in shaping human decisions and actions has been largely ignored by them. The message of these works is that to pursue national ‘progress’, the Siamese/Thai need to be more like the stereotypical Japanese, and become more disciplined, and patriotic, as well as cooperating for the national good rather than pursuing particular interests.