The Badger wrote:
As an aside, T3 stated that Judgement Day 'is inevitable' (which kind of contradicts the whole 'no fate but what you make' business, but so much for consistency). So no matter what Sarah did or who she phoned, Skynet would still be built and wage it's war.
I think they discuss this idea a bit. The general thought I took away from the third movie is that the idea of Skynet is 'inevitable' because its a government project. The US government wants a super smart AI controlling its nukes because apparently there is no Science Fiction in their world to tell them how bad an idea that truly is.
When Cyberdyne goes down for the count in the second movie, Sarah and team genuinely succeeded in changing their fate... by kicking the can down the road a few years. The government still wants their supersmart AI, so they throw millions of dollars at some other company, which puts together the new and improved Skynet. The one that doesn't run on easily targetable mainframes, because nobody uses those anymore. (Nice job breaking it, hero.) Had they somehow managed to destroy that system in its early stages also, the next iteration probably would have run off everyone's smartphones, embedding itself into social media sites.
So, yeah, Sarah and John changed their fate alright. They decided it was too easy the first time around, so its time to try on hard mode.