Markets brace for volatility this week as President Trump's new 15% global tariffs take center stage, following a Supreme Court ruling against his emergency levies. The tariffs, set to apply to all imports, mark a significant escalation in trade policy uncertainty. Congress could extend the duties after their initial 150-day period, potentially creating a de facto perpetual instrument, analysts warn. Simultaneously, the tech sector's AI momentum faces scrutiny with Nvidia earnings poised as a bellwether for market sentiment.

The chipmaker's results, expected Wednesday, could sway broader tech valuations already under pressure from AI adoption concerns. Dell's quarterly report Thursday offers another key data point, with server demand boosted by AI infrastructure spending but weighed down by rising memory chip costs. U.S.-Iran nuclear talks in Geneva Thursday add geopolitical risk, with Trump's March 1 deadline looming for potential military action, impacting oil markets and regional stability.