The Nasdaq Composite bore the brunt of the selling, tumbling 2.1% to 26,140.03, while the S&P 500 dropped 1.1% to 7,659.44. The Dow Jones Industrial Average held up better, slipping 0.3% to 52,002.41. All three indexes remain well off their 52-week highs set earlier this year, with the S&P 500 now roughly 2.4% below its peak of 7,844.52.
The trigger for the latest bout of risk aversion came from Tehran, where a senior Iranian security official said the country's armed forces have a prepared plan for confronting any new U.S. strikes. The comments coincided with reports of attacks on shipping vessels, raising fears that tensions in key maritime corridors could escalate and threaten the flow of oil and goods through the region.
Markets have grown increasingly sensitive to Middle East flare-ups given the potential impact on energy prices and global trade routes. Any disruption to shipping lanes near Iran could ripple through supply chains and fuel costs, complicating the inflation picture just as investors have been trying to gauge the path of interest rates. Technology and growth stocks, which tend to be more vulnerable to shifts in risk appetite, led Tuesday's declines, dragging the Nasdaq down at more than double the pace of the broader S&P 500.
The Dow's relative resilience suggests investors rotated toward more defensive, blue-chip names rather than abandoning equities altogether, a pattern often seen when geopolitical shocks hit markets that had been trading near record territory. Still, with all three major indexes retreating in tandem, the session reflected a broad pullback in risk appetite rather than an isolated, sector-specific move.
Investors will be watching closely for any further developments out of Iran, including confirmation of the reported shipping attacks and any response from U.S. officials. Escalation could pressure oil markets and prompt a flight to traditional safe havens such as Treasurys and gold, while a de-escalation or diplomatic signal could help stocks recover lost ground as quickly as they fell. For now, the uncertainty is keeping traders cautious heading into the rest of the week.