Comprehensive educational explainer on why the US dollar remains the center of global finance, despite no longer being backed by gold since 1971. The article outlines how dollar dominance rests on deep-rooted systems (pricing, trade settlement, lending, reserves) rather than commodity backing, and explains the cascading effects of Fed policy on emerging markets, exchange rates, corporate debt, and asset prices worldwide. Essential context for Thai SME operators with import/export exposure or dollar-denominated liabilities.