Wall Street trampled by AI sell-off; South Korean market plunges 10%

Global financial markets experienced a significant downturn on Tuesday, June 23, 2026, primarily driven by an AI-focused sell-off that began in Asia and spread to Wall Street. The South Korean KOSPI index plunged nearly 10%, triggering a trading halt, as major semiconductor companies like Samsung Electronics and SK Hynix saw their shares drop by over 12%. This substantial decline in South Korea was attributed to investor concerns over elevated valuations in AI and tech stocks, coupled with widespread profit-taking after a sustained rally.

On Wall Street, the tech-heavy Nasdaq Composite index fell by approximately 2.2%, while the broader S&P 500 also saw losses of about 1.4%. The market corrections were further exacerbated by growing investor anxiety surrounding the potential for interest rate hikes by the Federal Reserve and questions about the sustainability of high spending on AI infrastructure.