So here's what that means: Even if the person is NOT actively planning terrorist attacks against the US, because of the nature of terrorist attacks in general, merely his membership in an organization that IS planning those attacks meets the requisite definition of imminence.
So, basically, imminence does not mean imminent. And membership in Al Qaeda is seen as tantamount to being in a car when someone decides to shoot someone on the street, even if the other occupant had no knowledge beforehand that the drive-by shooter would act. Accessory to murder, drone edition.
And that is exactly what the Obama Administration is doing.
It still seems a rather slight of hand way to drone who you want to drone.