For a start, the drone strikes are at least claimed to be against strategic targets and not just indiscriminate killing of civilians. That's something that can't be said for the likes of the Brussels attacks.
Same goes with war crimes; cf. the U.S. attack on the Doctors Without Borders hospital in Kunduz, 2015. No matter what the facts are in that case, the U.S. is never going to admit responsibility for a war crime. Blaming the pilots for "human error", no consequences for any commanding officers, is the path they will take.
As for the indiscriminate killing of civilians, what else would you call the example from the article?
> in Pakistan, in attempts to take out 41 men, American drones actually killed an estimated 1,147 people (while not all of the 41 targeted figures even died).
Drone strikes that hit civilians and a specific target are sloppy assassinations, and terrorism.