As a special effects flick, I enjoyed it. As an extension to the Terminator franchise, it's yet another unnecessary addition to a story that already had its perfect ending in T2: Judgment Day. Still, I didn't mind another jaunt with John Connor, Kyle Reese, and the T-800. But the plot does suffer from severe logic issues that are impossible to ignore, especially as the movie's very premise basically draws the viewer's attention to them.
Rather than taking place at the brink of the timeline established as of the last movie, Terminator Salvation is set in 2018--more than a decade before John Connor sends Kyle Reese back to 1984 (and the script largely assumes that we already know the details and significance of that event). In a way, therefore, it actually occurs before the first movie, though, of course, it also takes place after the third. So now there are at least three temporal periods dragged into this mess of a plot, and those of us familiar with the previous films are aware of events on both sides of this installment's present. Things get really diabolical, however, when you consider that John Connor, as a character who lived through the last two movies, is also aware of those future events (and has apparently used that information to install himself as the prophet of the resistance).
Terminator Salvation is thus a movie focused on a war where both sides--John Connor and Skynet--already know how the next several years will play out, and presumably have known for as long as they've existed, since their futures also contain their origins. So what is even the meaning of anything that happens during this present period? What's done is done, right? Or are Connor and Skynet now five-dimensional beings, who somehow wage war across time, at all times simultaneously, even as they write (and attempt to rewrite?) their own histories? These are the maddening questions that this impossibly convoluted movie raises (unknowingly?) and seems at a loss to answer.
I understand there are problems intrinsic to any time travel plot, and the first two movies did not escape them. But they were still far simpler, more elegant affairs that left enough haze in the fate department that we didn't have to assume headache-inducing circles at work. T2 was even kind of intriguing specifically because the characters were working toward a paradox that they themselves could not fully puzzle out. Terminator 3 went back on that, and now, with this fourth film, the loops have become impossible to process, though I was fool enough to try. And none of the time traveling even occurs during Terminator Salvation!
I think what I was really hoping for was a Star Trek-style reboot that would have brought things back to a clean slate, not even necessarily for the benefit of new audiences, but because what came before had already gone too far. This movie is pretty much the opposite of that.
Terminator Salvation is otherwise noteworthy for being our first real look at future John Connor (albeit not all-the-way future John Connor), a once mythic character who, despite having barely appeared in past movies, became oddly revered within geek circles. (At least, in my travels, any "save the future" plot would always be described specifically as "a John Connor mission," despite the presence of arguably more prominent heroes in both of the first two movies.)
Christian Bale's performance as the living legend has been criticized as one-dimensional and monstrous, but I think his is the right approach. Because of what he's seen and what he knows, he's distant and maybe a little hollow, and there's a presence to him that's almost more than man. Witnessing his steely intensity, I did come to believe that he might be the one guy who could take on the machines.
Such a character would be hard to stomach as the lead, however, and the movie was at its best when it focused on the other heroes, leaving Connor as the story's true protagonist viewed from a distance. In fact, all other issues aside, I found the movie to be at its weakest during its third act, when it pushed Bale's Connor back to the fore, somewhat at the expense of the other characters.
Now, moving on, whatever happened to James Cameron? And why hasn't Matthew McConaughey ever taken on another Reign of Fire-type badass role?