Political disagreement routinely collapses not because of ideological distance but because participants occupy incompatible structural positions within the conversational space. This paper identifies five recurrent failure modes that undermine the possibility of shared understanding: divergent problem frames, mismatched levels of abstraction, identity binding, the dominance of emotional over propositional logic, and narrative compression. Each failure mode disrupts the formation of a common reference frame, converting discourse from epistemic exchange into symbolic or defensive behavior. By analyzing these mechanisms at a structural level, the paper clarifies why political conversation so often becomes unproductive and why conventional strategies for improving public discourse fail to address the underlying architecture of breakdown.