Pre-print: Retrenchment Signaling and the Erosion of NATO Credibility under Trump 2.0

In a newly published SSRN pre-print titled “Retrenchment Signaling and the Erosion of NATO Credibility under Trump 2.0”, Michal Smetana, Lauren Sukin, Marek Vranka, Ondřej Rosendorf and Isabelle Haynes examine whether the confrontational stance of the second Trump administration toward U.S. allies has undermined the credibility of NATO's collective defense commitments in the eyes of allies and adversaries alike.

Study design

The study employed a longitudinal survey design in which participants assessed the likelihood that selected NATO member states, as well as NATO as a whole, would send armed forces to defend Latvia in a hypothetical scenario of Russian armed aggression. To capture the breadth of audiences relevant for both reassurance and deterrence dynamics, the authors fielded three parallel studies across five waves of data collection between January 2025 and January 2026:

• Study 1 ("Allied Assurance Study"): a repeated-measures online panel across population samples in the United States, the United Kingdom, Germany, Poland, and Canada (N = 5,000 in the initial wave),

• Study 2 ("Allied Deterrence Study"): repeated surveys on representative samples of the Russian public (approx. N = 1,600 per wave), administered by the Levada Center,

• and Study 3 ("Allied Elites Study"): paired surveys of British parliamentarians (N = 100 per wave) and the British public (N = 1,000 per wave), complemented by a survey of German Bundestag members (N = 70).

Key findings

Trump 2.0 has decreased NATO’s credibility

Building on a novel theory of "retrenchment signaling," the article provides the first systematic empirical evidence that the credibility of NATO's collective defense commitments has eroded under Trump 2.0.

Across allied samples, trust that the United States would defend Europe from Russian aggression dropped sharply already in March 2025, following Vice President Vance's Munich Security Conference speech and the Oval Office confrontation with President Zelenskyy.

While non-U.S. allies were perceived as somewhat more likely to defend NATO territory, this second-order increase was substantively much smaller than the U.S. decline, leaving NATO's overall credibility lower at the end of the first year of Trump 2.0 than at its beginning. The authors interpret this asymmetry as a "substitution deficit": junior allies in asymmetric alliances can partially offset but cannot fully replace the reassurance provided by the leading power.

Declining deterrence power: Russian public perceives NATO as less credible

Moreover, the data reveal a distinct and arguably more troubling pattern among Russian respondents. While the initial Russian assessments registered both a decline in U.S. credibility and a compensating rise in the credibility of non-U.S. allies, from September 2025 onward credibility perceptions of both the United States and other allies declined in parallel, dragging NATO's overall credibility down with them.

The authors interpret this as evidence of a "strongest-link bias," in which adversaries tend to over-identify the credibility of an asymmetric alliance with the perceived commitment of its leading power, while discounting the agency of junior members. This suggests that U.S. retrenchment signaling may have even more damaging consequences for allied deterrence than for allied assurance.

Political elites in the United Kingdom and Germany show the same pattern

Their data also highlights that these dynamics are not confined to mass opinion. British parliamentarians were at least as skeptical about U.S. commitments as ordinary British citizens, and the assessments of German Bundestag members were statistically indistinguishable from those of their British counterparts.

These findings provide evidence of both elite-public alignment and trans-elite alignment across European NATO allies, indicating that the erosion of NATO credibility documented in the public samples translates directly into the realm of high-level policymaking on both sides of the English Channel.