This article discusses the grand strategy imperatives of 37 foreign policy experts in Washington, DC in response to President Donald Trump's nationalist challenge to the post-Second World War international order concept. Using an abductive reconstructivist methodology to analyse in-depth interviews, five grand strategy imperatives, or rules for action, shared by all actors were identified: safeguarding US global leadership, maintaining alliances, securing US prosperity, orienting at values, and believing in a mission. Based on the interpretation of these rules for action, four types of foreign policy experts were distinguished: nationalists, realists, pragmatic liberals, and liberals. The latter three expert types, altogether labelled globalists, were united in their opposition to the nationalists' demolition of the international order but divided along partisan and ideological lines about the meaning and implementation of the rules for action. Realists, pragmatic liberals, and liberals were also unsure of how to explain and respond to Trump's nationalism beyond a defensive or wishful hope to save the vestiges of an US-centric international order. The findings demonstrate the value of in-depth qualitative interviews for explaining elite beliefs and illustrate the rich insights for policy analysis that can be gained through this methodology.
