I wouldn't waste too much time attempting to figure out what ShadowFall's story will entail, based on previous games. There is a reason they are calling it "Killzone:Shadowfall" as opposed to "Killzone4." GG is moving away from the old story, and you shouldn't expect any of it to make any sort of impact on the overall plot of Shadowfall, other than the 30 second intro detailing what has happened since the ending of Killzone3.
Much like Mission Impossible: Ghost Protocol, it's a completely different plot with no strings attached, allowing for a "new" story to take form. From the looks of it, Shadowfall might be drawing more of a parallel to the historically ongoing Israeli/Palestinian tensions as opposed to the usual "space nazi" theme.
I wouldn't be surprised if this time around we actually get to play as Helghast, as well as the VSA/ISA shadow marshals.
Enjoy my icon.







