External Threat Increases National Identity, But Mostly by Fueling Outgroup Hostility

Why This Question Matters

Do external security threats bind deeply divided societies together, or do they simply sharpen existing cleavages? In highly polarized countries, scholars debate whether crises raise attachment to a common national identity (a superordinate identity) or instead increase hostility toward foreign adversaries. Nicholas Sambanis and Amber Hye-Yon Lee investigate this trade-off in the United States to show what ‘‘coming together’’ looks like under threat.

How the Authors Tested It

Sambanis and Lee deploy an experimental framework that manipulates perceptions of external threat and then measures shifts in identity and attitudes. The design isolates whether any increase in national identification reflects greater ingroup attachment (‘‘ingroup love’’), increased animus toward foreign others (‘‘outgroup hate’’), or both. The study focuses on the U.S. context, marked by high partisan polarization, to assess whether national and partisan identities compete or coexist under external pressure.

What They Measured

• Indicators of national identification and pride versus subordinate (partisan) identity salience.
• Attitudinal measures capturing hostility toward foreign outgroups.
• The extent to which respondents view partisan and national identities as compatible or in competition.

Key Findings

• Exposure to an external threat raises measures of national identification even in a polarized U.S. sample.
• The increase in national identification manifests primarily as greater hostility toward the national outgroup rather than as a pure increase in affectionate attachment to the nation.
• Strengthened national identification does not systematically reduce partisan attachment, provided partisans do not perceive their party identity as conflicting with national identity.

Why This Matters

The results refine expectations about crisis-driven unity: national identity can grow during external threats, but that growth often takes the form of outgroup hostility rather than enhanced inclusive national solidarity. The study highlights the importance of how identities are framed—whether national and partisan loyalties are seen as compatible—in shaping whether crises unify or further polarize a polity.