Stock market today, Jan. 21 -- The US stock market closed sharply lower overnight, with the S&P 500 slipping nearly 2% and the Nasdaq plunging close to 2.5%, marking the worst single-day fall since October. The global sell-off was triggered by renewed trade-war concerns after President Trump escalated tariff threats on select European nations opposing US control over Greenland, with proposed duties rising from 10% in February to 25% by June. This sudden escalation rattled risk sentiment across asset classes, leading to heavy unwinding in equities, a spike in US Treasury yields with clear bear-steepening across the curve, and a strong rush toward safe-haven assets. Gold surged to fresh lifetime highs above $4,777 per ounce, while technolog...