More political correctness in movies?: "Red Dawn" movie changes villain from China to North Korea

I guess that it just isn't politically correct to make the Chinese look like the bad guys.  China was the original bad guy, but after the movie was shot it had to be redone to make the North Koreans look bad. As the discussion at Box Office Mojo makes clear, this change hurts the plot and has made selling the movie more difficult "since the central conflict is blatantly absurd."  From Box Office Mojo (emphasis added):

Nearly three years after completing principal photography, the Red Dawn remake is finally reaching theaters (2,679 theaters, to be exact). The lengthy delay is being blamed on producer MGM's bankruptcy issues, though there was also the minor issue of having to change the invading force from China to North Korea in post-production. In comparison, the 1984 original (which earned $38.4 million, or $90.7 million adjusted for ticket price inflation) featured Russians as the villains, which brings to mind the biggest issue with this remake: in 1984, the notion of Russia invading the U.S. was far-fetched, but they were at least a global power, and the Cold War was still technically going on. While North Korea has been antagonistic towards the U.S., they don't even have the wherewithal to cause much trouble in Asia, much less stage an invasion of the U.S.  

Since the central conflict is blatantly absurd, the marketing has instead relied on vague patriotism, which just isn't as compelling. It's also emphasized the presence of Chris Hemsworth (Thor, Huntsman) and (to a lesser extent) Josh Hutcherson (Peeta), though star power tends to be an overrated indicator of box office potential. Distributor FilmDistrict is hoping for a debut in the high-teen-millions for the five-day weekend. . . .