I finnished Systemic Shock, and if anybody is interested, or for future reference if someone searches for this title:
I liked the book, although it is up to and including the end not in a post-apocalyptic, in my opinion not even an apocalyptic setting. Yes in the beginning it looks like an apocalypse, and yes, many people die, but the central government remains, and many countries remain more or less the same.
The second half of the book is nothing else than a "normal" war/agent story, with some mentioning of the big war. Furthermore the author continuously switches from "The US" to first person plural, sometimes even in mid-sentence, or even twice in a sentence.
nevertheless i liked the book enough to read the second one.