Yeah Action Comics takes place before Justice League does...and it's not six months that Clark has debuted but "several months" IIRC. Morrison has stated that at this point Clark hasn't uncovered his Kryptonian heritage yet so he doesn't know where his powers come from or where he is from. Martha and Jonathan are dead but we don't know for how long at this point. He also stated at SDCC that the Legion of Superheroes will be touched on in some way (he wouldn't say how) and that Jor-El and Lara would make an appearance in issue three.
I didn't think Clark was being a dick or arrogant at all. He's just very naive and idealistic as well as direct. He isn't at the point in his career where he thinks about the consequences of his actions. Morrison is very much playing on the word "Action" in this book.