After a century of demonising first Martians, then Nazis (who were airlifted into the U.S. with project Paperclip after the war), followed by Communists it seems Hollywood is back to demonizing non terrestrials with Spielberg's War of the Worlds and Harrison Ford's Cowboys and Aliens with Battle for L.A. which puts forward the idea that it's the corporations that need saving given that nobody trusts the military or the nation state. Give me space invaders any day.
