The Federation's objective is to demonstrate that it controls trade in the outer star systems. The queen refuses to capitulate, and the oppressed inhabitants suffer and starve. Admittedly, this is a small part of the story. The trade dispute is barely mentioned again. Lucas's ultimate purpose is to launch the Jedi career of Anakin Skywalker, who will grow up to be Darth Vader.
Traders tend to be peaceful.
It's hard to conduct business in the midst of combat. Tocqueville and others feared that commercial virtues would drive out martial virtues. Some early Americans shared this view. The history of trade is a history of peace and cooperation. Under that code, traders from different cultures and legal systems resolved their disputes peacefully, swiftly, and efficiently in the merchant-run courts.