Political scientists have long been interested in the American public’s foreign policy mood, but they have typically separated the microlevel question (who’s more likely to support isolationism?) from the macrolevel one (when does isolationism’s popularity increase?), even though public opinion is inherently a multilevel phenomenon, as the answers to these two questions interact. Showing how multilevel models can deal with the effects of time rather than just space, I find that both guns and butter drive foreign policy mood, but in different ways. When economic assessments sour, the public’s appetite for isolationism increases, but the impact of these individual-level perceptions is constrained by aggregate economic conditions, which are sufficiently salient that they are accessible irrespective of knowledge. The nature of the international security environment, however, predominantly affects foreign policy mood amongst high-knowledge individuals, thereby suggesting that low- and high-knowledge individuals’ foreign policy views are shaped by different situational cues.