War on Aisle 5: Casualties, National Identity, and Consumer Behavior

A growing body of research argues that external threats from the international system strengthen ethnocentrism and authoritarianism, personal values anchored in national identity. We evaluate a necessary implication of this argument, that these shifting values drive change in broader social behaviors. Our focus is revealed value change in a non-political setting: American consumers’ choice of supermarket brands that symbolize national identity. Our empirical analyses leverage US counties’ quasi-random exposure to US Iraq War casualties to identify the effects of local casualties on the weekly market share growth of “American” supermarket brands. We analyze weekly supermarket scanner data for a representative sample of over 1,100 US supermarkets and 8,000 brands. During 2003-2006, the weekly market share of American brands grew relative to non-American brands in casualty-exposed supermarkets. Variation in share growth across customer demographics is consistent with reactions to external threat. We rule out alternative mechanisms including partisan cues, other product characteristics, and animosity towards other countries. These findings strengthen IR’s theoretical microfoundations by showing that international politics can reshape values enough to change broader social behaviors.