Global markets reeled Monday as a renewed confrontation between Washington and Tehran sent oil prices surging and triggered a rout in tech stocks from Seoul to Silicon Valley.

Brent crude jumped nearly 10 percent to $83.30 a barrel after President Donald Trump announced a naval blockade of Iranian ports and threatened a 20 percent levy on all cargo passing through the Strait of Hormuz, the world’s most critical oil artery. Iran responded with defiance, warning it would not allow US interference and firing “warning shots” at two vessels attempting passage.

“The market is asking whether protection payments will go to Iran or the US—and how steep those costs will be,” said Andy Lipow of Lipow Oil Associates. Analysts warned the standoff could choke shipping and ripple across commodities.

The geopolitical shock weighed heavily on Wall Street, where the Nasdaq slid 1.6 percent. “Hostilities over the weekend are fueling a risk-off mood,” said Jose Torres of Interactive Brokers, noting doubts over any lasting truce given disputes over sanctions, nuclear policy, and control of the Strait.

Chip Sector Selloff

South Korea’s Kospi plunged 9 percent as semiconductor giants SK Hynix and Samsung tumbled more than 15 and 10 percent respectively. Hynix has now shed nearly 40 percent since last month’s record high, despite a blockbuster $26.5 billion US listing.

“The Kospi is a global barometer for chip sentiment—its collapse reverberates worldwide,” said Kathleen Brooks of XTB. Losses spread to Tokyo, where Advantest and Tokyo Electron slumped, and to US peers Micron, AMD, and Marvell, each down over 4 percent.

Investors are bracing for earnings from TSMC, ASML, and major US banks, with results expected to shape outlooks for both the AI boom and broader financial markets.

Market Snapshot (as of 2020 GMT)

Index/Commodity	Movement	Closing Level
Brent Crude	UP 9.6%	$83.30
WTI	UP 9.4%	$78.14
Dow Jones	DOWN 0.3%	52,498.64
S&P 500	DOWN 0.8%	7,515.34
Nasdaq	DOWN 1.6%	25,873.18
Kospi	DOWN 9.0%	6,806.93
Nikkei 225	DOWN 1.9%	67,242.73
FTSE 100	FLAT	10,498.29
CAC 40	UP 0.3%	8,364.65
DAX	UP 0.2%	25,114.25

Currencies: Euro/dollar slipped to $1.1384, pound/dollar to $1.3353, while dollar/yen strengthened to ¥162.43.