I wish to point out that, yes the parallels between the rebels and Viet Cong were there intentionally. But it doesn't make them the bad guys. Note that the Empire blows up Alderaan, killing all of their civilian population right in the first film. That is canon in all the versions. I don't know how the Empire-did-nothing-wrong folks all seem to consider that to be OK. Also the Emperor disbanded the democratic senate and replaced it with his hand picked lackeys. That is tyranny, not law and order.
The Empire has always been a bunch of cartoon villains who are just a step away from kicking puppies while twirling their moustache.