Korea's AI stocks now set the tone for global markets

South Korea's equity market, long viewed by global investors as a peripheral emerging market, has undergone a structural shift in its role within the global financial system. The transformation is rooted in the concentration of two companies—SK Hynix and Samsung Electronics—that control outsized shares of the memory chip supply critical to AI infrastructure. As AI investment has become the dominant theme driving equity markets worldwide, Korea's market has moved from the periphery to the center of daily trading decisions in London, New York, and Tokyo.

This shift is visible in the correlation metrics the body cites: the 60-day correlation between the Kospi and the Nasdaq 100 has reached 0.46, nearly three times the five-year average of 0.16. For portfolio managers, the practical implication is substantial. A Korean selloff no longer stays contained in Seoul—it extends immediately into Wall Street through SK Hynix's US listing and ripples across global chip stocks. The article quotes a London-based manager at PineBridge Investments saying "We are all Korean investors now," reflecting a genuine reordering of investment priorities.

However, the body notes that Korea's growing influence carries a structural weakness: the Kospi has become one of the world's most volatile major benchmarks, amplified by leveraged trading products. The recent 25% decline from the June peak—erasing $1 trillion（約160兆円） in value—demonstrates both the market's sensitivity to sentiment swings and the risk that excessive leverage can disconnect price movements from fundamentals. Even as SK Hynix and Samsung's pivotal role in chip supply suggests Korea will remain central to global AI investment, the volatility driven by leverage-fueled trading is creating friction for fund managers trying to distinguish genuine risk shifts from technical excess.