The US decision to double steel import tariffs to 50% could reshape global trade flows. This scenario analysis explores the full impact—on US steel prices, domestic production, finished steel demand, and import volumes. While some idle blast furnace capacity may be reactivated, long-term upside is limited by structural bottlenecks and high-grade capacity constraints. Key exporters including Mexico, Canada, the EU, Japan, and Brazil face renewed risk, especially with no exemptions currently confirmed under USMCA. As import volumes drop from 21 Mt to as low as 15 Mt, the shift will test the resilience of global supply chains and force trade realignment. Short-term domestic gains may be overshadowed by softer downstream demand and mounting uncertainty for international suppliers.