Possibly the most epic fictional America since... Amerika? Team America: World Police? Well, let us not exaggerate the setting too much (lest we make it come true!).
What makes this series and the larger franchise so interesting (and I suspect so successful), as I think is exemplified by this novel, is how it deals without apology in big, fantastical ideas. These become anchors for the story's conflicts, and both sides are done equally well- with clever mythical symbolism for magical processes and a quintessentially Japanese view of cyberpunk/near-future science fiction for the scientific innovations.
The balance is in the politics and the mundanely comic lives the characters are allowed in between calls to action.
In this particular story, media power in politics/the surveillance state and a magical control over humans derived from Russian fairy lore are the main points of focus, but we have plenty of more minor elements in play (like 'instinctual inconsistencies' in those imprinted with Accelerator's frame of mind, among weapons, magical countermeasures, and other things) and the story has definitely progressed to a significant conflict following World War III- this time from a split in the science side weakening Academy City's central control, precipitated by a rogue magic cabal called GREMLIN who at first seem dispossessed Russians from the losing side of the war.
The political tensions, beginning with internal strife in America, are interesting not least because Academy City's official position is as yet unknown, and we have in actions what the protagonist has been warned about countless times before about how magicians operate.
The constant action familiar from the war at the end of the last series doesn't leave as much space as some might like for the interesting encounters like Misaka Mikoto and Accelerator (who interestingly have just met for the first time in the Railgun S anime at the time I'm writing this) to greatly progress, but Misaka does express her resolve to follow Kamijou and set things right by the end. Kamijou Touma continues to be a somewhat odd case of a righteous hero who denies his righteousness while employing a righteous fist and owning all responsibility, and this could be a bit of an annoyance to some, but 'the boy' not being the whole focus is one of the best things about the series. He is what I call a 'displaced hero', in that his sense of self has undergone a crisis (because of the memory event in this case; but the general idea is as with Emiya Shirou in Fate/Stay Night- any trauma will do) and he clings to the support he has from friends and the responsibility he feels towards them and people in general, resorting to great ideals whether he acknowledges them or not. In this novel the burden he takes on is more obvious than before, since he sees his involvement as sought out this time.
As ever, the translation is at Baka-Tsuki.