Signaling Solidarity: Intra-Alliance Policy Signals and Public Preferences for Military Aid

When political leaders project consensus, the public is more likely to “rally round-the-flag” and support the national government's intervention policy. In contrast, competing narratives tend to create polarization and undermine the rally effect. US President Trump’s threats to suspend military aid to Ukraine created a rare window for studying the effects of competing elite cues on transatlantic public opinion. When Trump subverted solidarity norms and signaled that he would halt military aid for Ukraine, European leaders countered his message by declaring their steadfast support. Amid competing policy signals from home and abroad, does the public penalize foreign leaders for breaking commitments to external alliance partners? I fielded a preregistered survey experiment (n = 3029) in Germany and the UK just before the Trump Administration officially halted the flow of military aid to Ukraine, using vignette treatments that anticipated the actual policy signals eventually made by Trump and the national governments of both countries. The results show that competing signals from home and abroad create a permissive dissensus, allowing the public to express opposition to military aid by signaling that abandoning an embattled ally is an acceptable strategy for the alliance.