I'd play that game too. It'd be dark, controversial, and a political minefield, but I think a story-driven FPS set in a civil warring 2030 America would be awesome. The usual stories in CoD or Battlefield of USA military vs insurgents who are vaguely slavic or vaguely middle eastern have gotten stale for me - I'd love to see what game designers think all-American militia battles in NYC or Miami could feel like.

Again, it'd be super controversial and will probably never get made, but I'd play a game like that.