The rhetorical mode of action is the causal link that solves the double puzzle of Eastern enlargement. Through a process of rhetorical action, the interest- and power-based initial outcome of the CEECs' association to the EU and NATO was turned into the rule-based outcome of “membership.” In Part IV, I have tried to show both theoretically and empirically how a rule-based collective outcome is possible even if the individual actors pursue selfish and conflicting goals, the structure of bargaining power works against the rule-based outcome, and the rules cannot be enforced coercively. Drawing on the strategic conception of rules in sociological theory, I argued that, in a community environment, community members can be induced to refrain from pursuing their rule-violating preferences and to behave in a rule-conforming way when they are confronted with arguments that invoke their prior commitments, accuse them of acting inconsistently, call into question their reputation and credibility and thereby shame them into paying heed to their obligations as community members. In the empirical parts of the chapter, I showed how the mostly self-interested advocates of Eastern enlargement persistently appealed to the collective identity, the constitutive values and norms and the past promises and practices of the community organizations and how the no less self-interested “brakemen” in NATO and the EU were silenced – that is, they felt compelled to acquiesce in the enlargement initiatives of the “drivers” without being convinced of their claims.

The results of the NATO case study were inconclusive.