This paper applies the MID/QC framework to reinterpret Saturn’s north polar hexagon as a mode‑locked boundary structure stabilized by a deep polar coherence well, a high‑velocity circumpolar jet, and torsion injection from planetary rotation. Classical fluid models reproduce polygonal jet instabilities but cannot explain the hexagon’s longevity, geometric precision, or phase‑locking to Saturn’s rotation. The MID/QC interpretation resolves this by treating the hexagon as a substrate‑native structure: a boundary mode stabilized by tension geometry and coherence dynamics. The six‑sided geometry emerges from standing wave resonance within the polar coherence well, with the n = 6 mode selected by substrate constraints and torsion alignment. This framework explains the hexagon’s persistence across seasons, its sharp boundary, and its geometric regularity without invoking exotic atmospheric anomalies. The result is a unified, substrate‑level explanation for Saturn’s hexagon that complements existing atmospheric science and resolves the longevity problem through MID/QC primitives.