President Trump warned American oil producers Monday that he was watching closely for a crude price spike as the Middle East appeared close to a regional war, and he urged the Energy Department to “drill,

The U.S. crude oil price benchmark, West Texas Intermediate, fell 8% to less than $68 a barrel, the lowest level since last week. The global Brent crude price benchmark likewise fell about 8%. Major stock indexes ended the day in positive territory.

If oil prices are any measure, Iran just flinched. The price of oil tumbled Monday on a bet that Iran's decision to bomb U.S. and Qatari bases signaled it was not planning to do the one thing that could really hurt America: Shut down the flow of oil.