South Korea's KOSPI fell more than 8% on Monday morning, triggering its second circuit breaker — a 20-minute trading suspension — in four sessions. Samsung Electronics dropped over 10%. SK Hynix, the world's second-largest memory chipmaker, fell 12.3%.
South Korea imports 98% of its crude oil, almost all of it from The Gulf. The country consumed approximately 2.6 million barrels per day in 2025. At Monday's Brent price of $116, South Korea's daily crude import bill is roughly $300 million — up from approximately $175 million before the war began. That difference, sustained over a quarter, would strip roughly $11 billion from the Korean economy before it reaches consumers as higher petrol, heating, and manufacturing input costs.
The semiconductor sector is particularly exposed. Chip fabrication is extraordinarily energy-intensive — a single advanced fab consumes as much electricity as a small city. Samsung and SK Hynix together account for roughly 60% of global DRAM production and a substantial share of NAND flash. Their cost structures assumed energy prices in the $65–80 range. At $116 Brent, downstream electricity and petrochemical feedstock costs erode the margin advantage that Korean chipmakers hold over competitors in the United States and Japan, where energy mixes are less Gulf-dependent.
The circuit breaker mechanism itself is the signal. Korean exchanges trigger a halt when the KOSPI moves 8% from the previous close — a threshold designed for extraordinary events. Two triggers in four days means the market is not experiencing a single shock and adjusting; it is experiencing a continuous repricing that the normal trading mechanism cannot absorb in orderly fashion. The last time KOSPI triggered consecutive circuit breakers was March 2020, during the initial COVID-19 selloff.
