Seeing a bunch of people discussing the relationship between oil and the sharp decline in Korean stock prices, I suspect these people might have a mental problem. Bro, this is war. If a terrorist with nuclear capabilities goes crazy, wouldn't high-tech stocks also plummet? As for why the Korean index hit the circuit breaker, the explanation is even simpler. The top two weights in this index are Samsung and SK Hynix, which have been completely crazy these days, rising too much. They've risen so much that there's more room to fall, that's all.