Dr. C,

While contrary to what the director attempted to project, I do not think the corporation or any of its employees can be clearly argued to be 'bad guys'. The colonel was tasked with providing for the security of the operation. He had an extensive military background. His early experiences on Pandora (serious injury in his first several days, and having not been seriously injured in any previous operation) may have hardened his view and inflated the risk of the natives. He perceived coercion as the only effective method in removing the natives from the home tree (and he was right).

What undermined the decision-making process of the corporation was ignoring the scientific intelligence provided by Weaver's crew regarding the physical foundations of the local's culture.

The problem therefore is not one between diplomacy and coercion, but of uprooting the natives in the first place and destroying their environent with the follow-on economic exploitation. However, the film only hinted at the context of humanity's operations (calling earth a dying world), which can wildly alter the good/bad boundaries for everyone involved. Essentially, the main character condemned humanity to death.