US markets slide as semiconductor rout deepens on AI rivalry and geopolitical tension
Travelers surges on earnings beat while Nvidia and Alphabet falter amid valuation concerns and news of Chinese AI competition.
US equity markets declined sharply on July 17, 2026, as a deepening sell-off in semiconductor stocks overwhelmed strong performance in the insurance sector. The Nasdaq Composite fell 1.40%, the S&P 500 dropped 1.02%, and the Dow Jones Industrial Average slipped 0.77%. The decline extended a tech-led sell-off that saw the Nasdaq finish the week down 2.90%, driven by a combination of valuation concerns, geopolitical tensions, and fears regarding competitive dynamics in the artificial intelligence space.
The Philadelphia Stock Exchange Semiconductor Index has fallen more than 13% in the past month, weighing heavily on major chipmakers. Nvidia shares slid as investors rotated out of the sector, while Advanced Micro Devices and Intel also faced pressure. Alphabet shares declined following reports that the launch of its Gemini 3.5 Pro AI model would be delayed, adding to the negative sentiment surrounding the technology sector.
Investor confidence was further shaken by news that Chinese start-up Moonshot AI had released an advanced AI model designed to rival US firms. This development sparked concerns among investors that the Chinese competitor could undercut US sales, contributing to a broader risk-off mood in the market. This geopolitical friction was compounded by the re-escalation of violence between the US and Iran, which added to the uncertainty weighing on equities.
In contrast to the technology sector, the insurance industry outperformed significantly. The Travelers Companies jumped 9% after reporting a significant second-quarter earnings beat. Insurance peers, including Progressive and Allstate, also gained as capital rotated into defensive and value-oriented sectors. The energy sector was the only major sector to rise, while communication stocks and consumer cyclicals were the worst hit by the day’s losses.
Amid the equity volatility, gold prices rose 0.57% to $4,010.55, and the 10-Year Treasury yield climbed 0.02% to 4.55%. Analysts are questioning whether tech firms can continue their heavy spending on AI given the current valuation environment, with warnings of overextended premiums in the semiconductor space. Despite the recent pullback, the PHLX Semiconductor Index has risen by almost 63% year-to-date, suggesting the current volatility occurs within a broader upward trend.
