In countries that enclose disgruntled minorities linked to hostile powers through culture or location, defense planners face a Trojan horse dilemma. Can recruits from these groups be counted on to defend the state? This article is the first to examine the manpower policies chosen in response to this dilemma in Estonia, a small republic that inherited a large Russian population of Soviet-era settlers in 1991. It builds on historical records and recent opinion polls, which give cause for concern for Estonian defense planners contemplating the allegiance of Russian heritage soldiers. But elite interviews (N = 29) suggest that force professionalism and republican rhetoric obstruct fifth column fears from influencing manpower policies. Officers created institutions that permit recruits to prove themselves on merit while the republican citizenship discourse deterred politicians from singling out “ethnic soldiers”—thus facilitating integration.

What makes individuals willing to defend their (adopted) homeland as their own? This is an essential question for all diverse societies. We turn to the case of Estonia, which inherited a sizable Russian-speaking population after the fall of the Soviet Union. Using recent polling data, we test demographic and attitudinal predictors of defense willingness among the first generation of males that have been raised in the republic since the restoration of independence. The results enable us to unpack differences between Estonian-speakers and Russian-speakers, as well as disagreements among the latter, which shed light on the state of social cohesion in Estonia’s national fabric.