The Declining Reliability of U.S. Foreign Policy and its Domestic Sources Under Trump II

The 2024 U.S. presidential election and the second administration of Donald Trump have instilled unprecedented uncertainty into international politics, with profound implications for transatlantic relations and global alliance structures (Wiedekind and Bller 2025; Ciolan and Moyer 2025).Under Trump, American commitment to the Liberal International Order (LIO) has all but completely given way to material primacy and indifferent transactionalism as guiding paradigms in U.S. foreign policy.Some scholars have sought to explain this shift by highlighting the 45th and 47th president's worldview, comprising of populist nationalist traits (Lfflmann 2024).Others have underscored the power dynamics at the international level, in particular the hegemonic decline of the U.S. in view of China's rise, which reduces the hegemon's willingness to contribute increasingly scarce resources to uphold the international order (Heinkelmann-Wild et al. 2021).Both strands of explanations, rooted either in first (individualistic) or third (systemic) image analyses of IR, offer important insights into understanding U.S. foreign policy in the age of Trump.At the same time, we argue that a key piece of the puzzle to explain this foundational shift is the domestic setting of U.S. foreign policy, actively enabling Trump to implement his "America First" agenda (Biegon and Hamdaoui 2024).While the contestation of traditional foreign policy principles and norms has been in the making over the course of the last two decades (Kupchan and Trubowitz 2010;