The Week That Was — And the Friday Morning That Changed the Mood
The week ending May 15, 2026, had been, by the numbers, one of the most remarkable in the modern history of US equity markets. The S&P 500 and the Nasdaq Composite each set fresh all-time closing records on three separate occasions within five trading days. The Dow Jones Industrial Average climbed back above 50,000 for the first time since the Iran war began in late February 2026. Cisco Systems surged 13 percent on blockbuster earnings. Nvidia extended a winning streak to six consecutive sessions on the back of the US government's approval of H200 chip exports to Chinese companies during Trump's Beijing summit. Cerebras Systems debuted on the Nasdaq and immediately surged 68 percent on its first day of trading, pricing at $185 per share and raising $5.55 billion in the year's most significant technology IPO. The S&P 500 and Nasdaq were each on pace for their seventh consecutive positive week — the longest winning streaks for both indices in years.
And then came Friday morning, May 15. US stock futures opened the pre-market session in a distinctly different mood. Dow Jones Industrial Average futures fell 132 points, or 0.26 percent. S&P 500 futures dropped 0.5 percent. Nasdaq 100 futures declined 1.4 percent — the sharpest pre-market retreat of the group. The immediate catalyst was a combination of factors: the partial unwinding of the optimism that had driven markets higher through the Trump-Xi summit, renewed anxiety about the state of the Iran ceasefire and the continuing blockade of the Strait of Hormuz, and a broader profit-taking dynamic after a sustained period of record gains in a relatively narrow set of technology and AI-linked stocks. The mood in global markets on May 15 morning was not panicked — but it was noticeably more cautious than the celebratory atmosphere that had prevailed through the week's trading sessions.
Europe Slumps: London, Frankfurt, Paris, Milan All Down
European equity markets bore the brunt of the Friday morning risk-off move. The pan-European Stoxx 600 index declined 1.3 percent in morning trading on May 15, with virtually every major European national market moving lower simultaneously. London's FTSE 100, Germany's DAX, France's CAC 40, and Italy's FTSE MIB all opened in negative territory and failed to recover their losses through the morning session. The breadth of the European sell-off — affecting all major markets and most sectors — indicated a broad reassessment of risk appetite rather than a sector-specific or country-specific concern.
Mining and metals stocks were among the hardest hit in Europe. Antofagasta, the Chilean copper mining company listed in London, fell 7.9 percent — one of the largest single-session declines for the stock in recent memory. Fresnillo, the Mexican silver miner also listed on the London Stock Exchange, dropped 7.7 percent. Both companies declined in response to a fall in precious metal prices: gold sold off on the day as a stronger US dollar reduced safe-haven demand, and silver also retreated. Oil prices, by contrast, edged higher amid the continuing impasse in Middle East peace negotiations — a divergence between energy and metals that reflected the specific geopolitical drivers of each commodity's current pricing. The European banking sector also underperformed, as rising energy prices and continued inflation concerns put pressure on margins and lending outlooks for financial institutions across the continent.
South Korea's Kospi Tumbles More Than 6 Percent
The most dramatic single-market move among Asian and Pacific bourses on May 15 was the collapse of South Korea's benchmark Kospi index, which fell more than 6 percent after having reached a fresh record high earlier in the week. The small-cap Kosdaq index also declined 2 percent. The Kospi's sharp reversal came in the context of an ongoing and escalating labour dispute at Samsung Electronics, South Korea's largest company by market capitalisation and one of the most systemically important semiconductor manufacturers in the global supply chain. South Korea's finance minister Koo Yun-cheol had warned on May 14 that a potential strike by Samsung workers — with more than 41,000 workers expected to participate in a walkout that had been first announced at a rally on April 23 — could pose a major threat to the country's economic growth, its exports, and its financial markets. The finance minister's warning, combined with the broader global risk-off move on Friday, was sufficient to trigger the kind of concentrated selling that produces double-digit percentage moves in individual sessions.
Japan's Nikkei 225 declined 0.9 percent, with the broader Topix index ending flat. In Australia, the S&P/ASX 200 lost 0.25 percent. Hong Kong's Hang Seng index slid 0.39 percent, while the CSI 300 — China's benchmark index of the 300 largest mainland-listed companies — opened flat. The relative stability of Chinese mainland markets, even on a day of broader Asian weakness, reflected the specific support provided by the conclusion of the Trump-Xi summit and the positive framing of its outcomes by Chinese state media. India's Gift Nifty futures indicated a cautious opening for the Nifty 50 benchmark, consistent with the broader regional trend of subdued risk appetite on May 15.
Oil Rises: Hormuz Remains the Wild Card
Crude oil prices moved higher on May 15, maintaining the elevated levels that have characterised the energy market throughout the US-Iran conflict. Brent crude held firmly above $100 per barrel, with the specific level depending on the time of day and the latest diplomatic signals from the Middle East. West Texas Intermediate also traded at elevated levels. The White House's announcement at the Trump-Xi summit that both sides had agreed the Strait of Hormuz must remain open was treated by energy analysts as a positive directional signal but not as a resolution of the underlying supply disruption — approximately 1,600 commercial vessels remain stranded in or near the strait, and Iranian forces have not indicated any intention to unilaterally lift their restrictions on commercial traffic absent a comprehensive peace agreement that addresses Tehran's core demands.
Shell CEO Wael Sawan's warning, issued earlier in the week, that the world might have produced one billion fewer barrels of oil as a consequence of the Iran war, and that shortages could emerge within weeks rather than months, continued to reverberate through energy market pricing. Inflation expectations, which had already been elevated by the April CPI reading of 3.8 percent — the highest since May 2023 — and the PPI reading of 6 percent year-on-year, remained a concern for bond markets and for the Federal Reserve's policy calculus. The utility sector remained under pressure from rising Treasury yields, with the 20-year and 30-year US rates hovering above or near 5 percent and making the high dividend yields of utility stocks relatively less attractive to income-seeking investors.
The Week's Record Run in Context: AI Bull Market Remains Intact
Despite Friday morning's pullback across global markets, the week ending May 15 represented a net positive outcome for the AI-driven technology bull market that has defined the first half of 2026. The S&P 500's anticipated seventh consecutive positive week — if it holds through the May 15 close — would match the longest winning streak the index had recorded since late 2023. The Nasdaq's seventh consecutive weekly gain would equal its longest streak since October 2024. The semiconductor index remained up approximately 60 percent year-to-date, reflecting the extraordinary and sustained demand for AI hardware, data centre infrastructure, and advanced chips that has driven the sector's outperformance throughout the year.
Cisco's 13 percent surge following its blockbuster earnings report was the week's most prominent single-stock event after Nvidia's continued ascent, and signalled that the AI investment theme is broadening beyond pure-play chip companies to encompass the networking and infrastructure firms whose equipment underlies the data centres and cloud computing platforms on which AI systems actually run. Applied Materials, the semiconductor equipment supplier, climbed approximately 2 percent in after-hours trading following its own solid quarterly results. Figma, the collaborative interface design company, surged 10 percent after-hours on revenue beats. The pattern of strong earnings from technology-adjacent companies reinforced the view that the AI capital expenditure cycle — the multi-year wave of corporate and government investment in AI infrastructure — remains in its early and accelerating phase, providing fundamental support for the technology sector's valuation premium even in weeks when the broader market pauses to reassess its risk appetite.