DOW down 2025. Many analysts are saying the reason is the oil war between Saudi and Russia. That may have been one of the triggers but certainly is not the reason. They need a scapegoat, preferably one that is temporary, so people overlook the real problems, have good future expectations, and do not blame those really responsible. Cheaper oil and gas would help many countries in economic output and not hurt the US that much. JMHO
Perhaps they are concerned that oil price will affect the dollar as a reserve currency but an oil war would not ensure that. The rest of this week will tell a lot.
Edited to add: If the oil drop is expected to trigger collapse of DB and others because of derivatives, then it makes sense but they have to know things I do not. That is something to keep an eye on.