why launch ASCM from non-friendly airspace given the missile has >1000km range?
0)Target data isn't always precise. Generally, on the contrary, it isn't. It means your aircraft will perform part of the search on their own, possibly under attack. You won't find a thing from 1000 kms, if target isn't ignorant.
1)Even if you have such a data - your task isn't just to launch a Salvo, but to make sure what missile seeker will home on target. And targeting data against moving targets ages very fast(depending on targets' and weapons' velocity, as well as weapons' ability to acquire target)
Missile seekers aren't exactly the most powerful pieces of radar tech in existence, their search capabilities have their limits(very serious ones). Naval targets, on the other hand, tend to move fast(up to 50 km/h), have strong EW suits, and so on.
Basically, launching a subsonic missile from 1000 kms against anything suspecting attack is nearly a waste, if there won't be mid-course corrections.
More often than pilots would like to - there won't be any, be it for lack of suitable reconnaissance assets or enemy interference.(say, Growler completely jammed your corrections)
Thus subsonic ASCMs have much shorter ranges(typically - below 250 kms), and supersonic eat too much fuel. LACMs are another case, i'll address it later.
2)If target is of high value, it can mimic something else(or, the other way around, something can mimic your target). Thus - targets sometimes have to be positively identified. In some cases you'll have to do it visually. Sad, but true. Also, many missiles still tend to distinguish false targets(EW) from actual ones worse than human.
3)range of 1000 kms is given for certain set of conditions, including launching aircrafts' velocity and altitude. And flying high means being visible to everyone.
4)ALCMs are another story. While their targets don't run(and they're typically used against something found in advance) - they typically can't fly straight to the target. They have to avoid low altitude radar coverage, fly through waypoints and so on. All this maneuvering consumes lots of range.
5)1000 kms isn't exactly safe, even if fighters are based around or on target location.
On the other hand, subsonic bomber isn't just an airliner with rockets.