Previous research has examined the United States’ strategy for supporting Ukraine during the ongoing war with Russia while seeking to avoid escalation with Moscow. It is often suggested that the U.S. has used a gradual learning-by-doing approach driven by concerns about Russian escalation. This quantitative study explains variation in the composition of U.S. military materiel support to Ukraine between 2022 and 2024 through the concept of strategic signalling, using escalation- and needs-based logics.
Based on monthly observations the analysis suggest that U.S. support did not follow a reactive pattern in response to Russian nuclear threats or changes in battlefield intensity. Instead, variation is primarily associated with time, indicating a gradual calibration of assistance. This points to a measured support strategy and opens avenues for further research into the underlying mechanisms shaping the temporal dynamics of military material assistance.