This paper contributes to disinformation research by showing how identity-driven controversies are prime vehicles for circulating disinformation. We theorize disinformation as an engagement-driving process that encourages participation in culture wars through any argumentative means—including not only falsehoods but also truths, half-truths, and value-laden judgments—exploiting them rhetorically to contradict perceived opponents. Empirically, the study reports on the flat Earth echo chamber on YouTube, a controversial group arguing that the Earth is not round but flat. By analyzing their rhetorical strategies, this study shows how flat earthers animate and stoke identity-based grievances. As grudges intensify, back-and-forth argumentation becomes a form of ‘knowing’ in the world, which the echo chamber weaponizes rhetorically. The resulting argument becomes impervious to fact-checking because it is not about facts (logos) but grievances (pathos) and group identification (ethos). Hence, this investigation conceptualizes disinformation as rhetorical acts that persuade in and through the contradictions of identity work, thus animating and co-creating culture wars. The paper proposes a two-phase framework conceptualizing how disinformation disseminates in social media through echo chambers. In the “seeding” phase, malicious actors strategically insert deceptions, masquerading their legitimacy (e.g., fake news). In the “echoing” phase, participants co-create a confrontational fantasy that disseminates disinformation argumentatively.