The tech-stock party hit a wall on Tuesday as a 10% crash in South Korea's KOSPI — sparked by reports that SK Hynix is slowing AI memory chip expansion — crossed the Pacific and slammed into Wall Street. The Nasdaq Composite plunged 579 points (-2.2%) to 25,587, the S&P 500 dropped 1.4% to 7,365, and the NASDAQ 100 sank 2.6%. It was the kind of day that makes you check whether your stop-losses actually work.

What's Losing Ground

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