Terminator Salvation : The Future Begins

[LOC Veteran]

Yes but in the scene where Serena Kogan's character as SkyNet tells Marcus what's going on, she tells him he's succedeed where SkyNet has failed "time and time again" to kill John Connor. If it's 2018, how does SkyNet know they've already went back in time 3 times in the past, if that's in 2036 or whatever? As a casual facts kinda guy I can let that sort of thing slide, but it's really bugging me because I feel they are just not going to address it/explain it in the next movie(s).

[Xero]

It's because the future where they sent them back no longer exists. The moment they sent them back the altered the timeline. So the second Terminator they sent back, they knew they already failed. Also explains how they were able to create a significantly more advanced Terminator in less time. Marcus was their 4 attempt on his life. If they hadn't sent any Terminators back to kill him then you'd be right, they shouldn't have had a clue who he or Kyle was. T1 started the chain reaction. The TV show helped explain the alternate timelines pretty well with Derek and Jessie. Derek came back before her, changed the past so when she came back her memories were different because the future she was from was different than the one Derek came from. So technically speaking they won't try sending another T-800 back to kill Sarah in this timeline because they know it doesn't work.

Also worth noting in T1, it was their last attempt at survival to send their best model the T-800 back to kill Sarah. Even in T2-T3 the altered timeline is present. The T-1000 a more advanced Terminator in less time then it originally took to create the T-800. Then with the T-X in T3. We see this same trend of advancement in Salvation where the T-800 was finished significantly sooner than expected. Also makes room for T5 where the machines have advanced enough to send through entire ships instead of just the organic organisms. Each time they go back they leap frog their advancements.

As confusing as it can be, if you think about it enough, it does make sense. The problem lies with ones perspective of time travel. Is it an endless loop or does it change the outcome of the future.