The British government pursued policies toward its colonies that it thought reasonable and just in the aftermath of the Treaty of Paris. Why did many colonists see these policies in an entirely different light?
After the French and Indian War the British government enacted a number of policies that were meant to get more money out of the colonies. The government felt that the colonies had not been helping Britain enough. It felt that the colonies ought to pay their fair share of the costs of the war. Therefore, they started taxing the colonies more and they started trying to enforce laws like the Navigation Acts that had been meant to restrict colonial trade with other countries.
Many colonists disliked these laws. They felt that the laws were contrary to their rights as British subjects. They felt that the British government did not have the right to tax them without their consent. They felt that the British government did not have the right to impose internal taxes, like the Stamp Tax.
The colonists also disliked the enforcement of the British laws. They disliked this because the British had not enforced the laws for a long time. Because of this, they had come to feel that the laws did not exist and would never be enforced. When the British started to enforce them, the colonists felt like their rights were being taken away.
Overall, then, the American colonists felt that the British policies were taking away their rights even though, to the British, these policies were perfectly justified.