The basis of Temporality is that all things are linear. The basis of causality is that all things are reactionary.
The prospective notion behind Terminator's use of a time portal is a combination of the two.
Thus 'once' you have a future war where a rogue computer takes over the world and 'the last of humanity objects' you will always have that timeline (and indeed as Skynet loses in either one it doesn't matter in an ultimate last-mand-standing sense for the humans, we've done worse to ourselves before).
What Skynet wants to do is prove that, once branched, time (or fate if you prefer) can be be _collapsed_ towards either a remerged or divergent third eventuality of it never having to fight John Connor at all.
They way it achieves this is to go back into a 'common past' and refuse to allow the diversity of fates events to happen.
Given that there may indeed be some 'Cosmic DNA Strand of Conscience' based on some kind of super physics that refuses to allow such a massive rewrite, the method the Computer has chosen is in fact the hardest because, by attempting to shut down or isolate one fate path it is in fact supplying the recombinant energy that drives their unavoidable fission.
When looked at from this standpoint, 'success' for Sarah Connor is equally dicey because anything she does to eliminate the threat at the second stage of event sequence evolution again stretches not only forward but BACK to the point where causality broke open multiple destinies to begin with.
The key understanding however is that Sarah has a place in ALL these futures:
1. Never having met Kyle, she lives, dies and is buried.
2. Having met Kyle, she loves, reproduces and has HIS son before killing Kyle (as we know him) by destroying Cyberdines parallel array chip.
3. Having met Kyle, she loves, reproduces, hides and raises the future of humanity.
Death of Kyle or otherwise as long as she lives ALL THREE of the known futures survive.
And the most you can do is remove Kyle which removes Kyle's son.
While again, AS LONG AS she lives 'undisturbed' so does at least the potential of Skynet's baseline parallel array chip being first-designed.
This is where you have to wonder at what kinds of aggressive-resolution AI logic is present in a military computer systems 'orientation' towards a combat decisioning that it would seek to destroy rather than moderate the effects by which it's existance is put in jeopardy at a terminus point 'upstream' from the causal-temporal layer that assures it's basic creation.
If Skynet supplied itself with the data to exist before it existed (taking it's design formats if not software 'memories' back in time) it wouldn't matter if it had been 'unplugged' at point-X.
If Skynet supplied itself with the strategic outcomes of future wars by sending back a Terminator with a 'this is how it will be' set of datapoints WITHOUT altering Sarah's keystone (three way arch) fate split status then it could kill her AND Kyle with ease at a point later in sequence where fate meant less.
If (under similar Terminator-from-past warnings) Skynet allowed itself to be portrayed as the 'innocent victim' simply executing militaristic mission orders it had no control over (the HAL-9000 argument) it could present itself to humanity as a last-best-hope chance for BOTH 'species' to survive.
Skynet because of it's limited (though presumeably burgeoning) ability to complex-articulate itself through the ONE Terminator then being reverse engineered. Humanity because such basics as food, clean air and water, reliable longterm power and non-contaminated living areas would be _utterly_ dependant on heavy mechanical assets and the initial construction of an assembly line and production tooling by which they could be created.
The (ironic) compromise likely being the destruction of the T-800 line and the 'certification as man rated' codependent-by-design construction of heavy construction/demolition type machines in removing and burying _vast_ quantities of hard rad rubble and topsoil while planting hardy grasses and fast growth trees (and seeding the oceans with low light and cold tolerante microplankton) to help provide at least a baseline by which the environment could regenerate while living in bunkers with 'canned food' that would also have to be collected by radiation proofed drones.
It is simply amazing how rapidly man, without the specialist-skill leverage of other men, descends into a barbarian state. While this is not necessarily a 'bad thing', where the environment no longer supports the simple living styles possible with limited technology, a multi-PhD Super Computer with all the knowledge of every on-line library before the Apocalypse would become more than a God for it's ability to dispense 'higher learning' enhanced survivalism.
Now, for MY question:
In any organization but particularly a military one, The First Purpose of delegated authority is NOT efficiency but _survival_. Particularly in a Top Down command structure where there is very limited redundant damage control, the absolute divorcement of hand-from-mind is a NECESSITY to avoid ultimate decapitive disruption of focussed goal achievement.
Thus, IMO, John Connor is either exceptionally STUPID or /very selfish/ in demanding that his father's contribution to his grandiose life role be based on 'one night of passion' rather than a microfiche-under-fingernail (or any other orifice or crack) by which Sarah Connor could have access to all the lotteries, sporting events, stock reports etc. for the YEARS of interval by which she could prepare a series of _impersonal_ attacks upon Cyberdine.
From a position of hire-not-fire weaponed mercs.
Or lawyers.
In this way, even if Kyle dies (and my first response would have been to hire a private charter airplane, truck or train that would take me a thousand miles away from California) without impregnating her she can continue the battle from a position of isolated but empowered (multiple if need be) attacks without causal or temporal worries as SKYNET built the time portal and SKYNET exists, at least as a prototype idea, in the past wherein all that Sarah Connor's manifest wealth could be sub-timeline shielded by the reality of their dual existance.
Or even exclusive ownership.
And anything Sarah does to destroy or alter Skynets existance can only reverse cascade back to a point at which SHE still exists and all that Skynet does to stop her is foiled 'in between'.
Again, it should not be understated that the inherent capability behind a Skynet or even Terminator type system is not evil. Indeed, it may be less corrupt and ultimately short-sighted (say mortal) than our present 'all too human' governing and capitalistic labour enforcement socialization styles.
But the difference between a strategic-AI counselor and a defense system with a deliberate doberman 'personality conflict' of intellect lies in the software by which it is taught it's function.
And thus whether you destroy the hardware or the designer if the INTENT is retained, you will only face another reiterative misuse of technology idiocy a few years down the road.
But if you rewrite the function, then you can still invest in everything from medicine to sociology to enduring power sources while providing an 'endpoint continuance through symbiotic enhancement' of BOTH artificial and biologic lifeforms.
Saberist.