What's going on?

The price of a barrel of Brent crude oil hit its highest in a year on Monday, after a drone attack on Saudi Arabia over the weekend put the slippery elixir�s supply in its crosshairs (tweet this).

What does this mean?

The drone strike � which a Yemeni group has since taken credit for � was aimed at oil giant Saudi Aramco�s facilities, including one terminal capable of meeting 7% of the world�s oil demand. Saudi Arabia said the attacks were intercepted, so there was no actual disruption to the supply of oil. But the risk alone � not to mention the threat of retaliation or another attack � was enough to send oil�s price above $70 a barrel for the first time in over a year. And yes, that is d�j� vu you�re feeling: a similar price spike happened after an American airstrike in January last year.

Why should I care?

For markets: The damage might already be done.

It didn�t take long for the oil price to drop again, but just the prospect that limited supply would push prices higher could cause problems for stock markets. Oil�s essential to everything from toys to jet fuel, which means the more expensive it gets, the more expensive they get. That increase in inflation raises the likelihood that near-term interest rates will climb too, making high-growth and high-multiple stocks � like tech companies� � look less attractive.

The bigger picture: Speaking of jet fuel…

The toing and froing of oil�s price has major implications for the earnings of hard-hit airlines, which generally hedge their fuel costs to lock in prices. If the economy recovers faster than anticipated, those airlines could find themselves forced to buy jet fuel at prevailing � read: higher � prices. Still, a quicker-than-expected recovery is a nice problem for airlines to have these days, which might be why 77% of authors on data platform Nobias Financial are positive on the US�s biggest: Delta Air Lines.