The Good Shepherd, Green Zone, The Adjustment Bureau, the Bourne series, all drive this point home aggressively. Even his roles in The Informant! and The Departed support this theme.
Damon's acting career and his ideology are in perfect lockstep.
Well one had to expect that the Bourne series would be left wing tripe since it was written by Robert Ludlam.
That hack just kept cranking out anti-US screeds disguised as spy novels. Every story was pretty much centered on how the CIA was Evil, incompetent, and nearly omnipotent. He never quite grasped by the latter two points were mutually exclusive, so the stories were all incoherent.
The Good Shepherd, Green Zone, The Adjustment Bureau, the Bourne series, all drive this point home aggressively. Even his roles in The Informant! and The Departed support this theme. Even his roles in The Informant! and The Departed support this theme.
In The Informant! Damon's character's conspiracy theories turn out to be his own crazy inventions. There's a few more twists than that, but the movie doesn't quite fit your thesis. Whatever corruption the business men were involved in is only the set-up for a movie that takes a very different turn.
In The Departed the conspiracy is composed of traditional bad guys: the kind of mobsters who've been villains in film for eighty years. Again, there's more to it than that, twists and connections that complicate things, but really a movie showing corruption in Boston isn't exactly an indictment against the United States (Ask Howie Carr).
Those two pictures are more complicated than your view of them. I'm not saying that your general idea is wrong, but you take it too far.
FWIW: I saw The Adjustment Bureau this weekend. What an awful picture. Message: God wants us to make Andrew Weiner President. Or something along those lines. Apart from that, the movie would have benefited from the futuristic setting of the other films based on Philip K. Dick novels. Apparently the original story had a science fiction feel that was lost in the movie.