<h1>Tariffs on steel and aluminium trigger trade tensions, prompting broad market selloff and cross-border investor withdrawals.</h1> The United States' imposition of 25 per cent duties on steel and aluminium imports, together with the European Union's vow of a firm response, establishes a legal-policy confrontation over import duties and potential retaliatory measures. These trade-policy moves are identified as the proximate cause of rapid market volatility, triggering broad equity selloffs, accelerated foreign institutional outflows, and concentrated sectoral declines that reflect the market transmission of tariff-driven regulatory risk.