I didnt know that it hadnt been shown in Japan yet, because I dont follow the Anime as closely as I used to.
Well, clearly you didn't do enough research if you didn't even bother checking whether one of the cornerstones of your argument (that us not seeing the Rocket/Plasma episodes in English was the fault of the EVIL AMERICANS OPPRESSING US ALL) was true or not.
In any case, you're missing the point. The Rocket/Plasma episodes not being shown (or anything in B/W, for that matter) has NOTHING to do with 9/11. It has everything to do, however, with the earthquakes/tsunami from last year happening just as those two episodes were about to air, and the Japanese not airing them to further distress people.
I doubt they'll even be shown, Ash and co. are too far away from the two big cities (Castelia and Nimbasa) by this point for the Rocket/Plasma episodes to make any sort of sense.