Read my part two about 2 pages back. To me T2 ASKED the question can you change it. But it never showed anything. Nor did it flat out say they changed the future, it was always asked as more of a question. If they would have changed it they would have kept the original alternate ending in, where everything was fine. Cameron cut it out to leave it ambiguous. It is possible. But it is also possible, that them destroying the arm and chip, and Dyson was just a step forward and was always going to happen that way, they just did not know they were helping fate along.
I took T2 that way, but of course T3 changes that. But I explain that more how I see it a few pages back, and how a lot of other fans feel too. Not everyone though.
Okay so having a day to think about this...here is my take on the whole Terminator idea and how it relates to your perspective.
As you said in T1, the message behind it is that destiny is destiny and that no matter how hard you fight it, everything will happen the way its supposed to.
T2 was the idea of questioning whether or not destiny can be changed and whether it was possible.
T3 (FOR ME) was the idea of coming to the realization that no matter how much you may try to change your destiny you simply cannot escape it.
TS was the aftermath of what has happened since you have tried to alter your destiny.
We all have varying interpretations of Time Travel...obviously none of which can be proven or disproven. I think where you and I disagree Solidus is when it comes to this subject. You seem to believe in the theory of what was established in the first two Terminator films where the timeline seemed to play in a continious loop.
My argument is that with the inclusion of T3 and TS it simply destroys that idea and presents the "Butterfly Effect," the notion that by attempting to change and alter the future they have actually made it worse than what it originally was.
For me, in an original timeline, Kyle Reese was not John Connors father however by sending him back to 1984, it created an alternate timeline where he is. In relation to TS, all of the previous tampering in the past has created a world where Skynet knows about Kyle Reese and John Connor, where the T-600s are not what they were originally described as and where a T-800 is developed nearly 10 years ahead of time.
The future we are presented in TS is not the future the Kyle Reese in 1984 is familiar with...there are similarities sure, but by simply going back in time he essentially created a whole new future entirely different than the one he came from. The concept they used in the latest Star Trek film is the best way I can describe my feelings towards the Terminator franchise...esp. after watching Salvation.
As is the case in that film...everything that is destined to happen WILL HAPPEN i.e. John becoming the leader of the resistance (as Kirk became Captain of the Enterprise), T-800s, sending Kyle back to 1984...it will simply take a whole lot longer and very different circumstances.
So what i'm saying is, as established in T1 and T2,
what is destined to happen will happen. But as established in T3 and TS, thanks to the constant alterations in the timeline,
the journey to get there will be much more complicated than originally planned.