Final answer:
The colonists moved towards independence due to actions like taxation without representation, unaddressed petitions for redress, and British aggression at Lexington and Concord.
Step-by-step explanation:
The colonists believed it was necessary to declare independence from Britain due to a series of actions that made it clear that their rights and interests were being ignored. A significant factor was taxation without representation, which violated the principle that only bodies representing the taxed should enact taxes. The Stamp Act and other measures to raise revenue without the colonists' consent were seen as unjust.
Additionally, when the colonists petitioned for redress, their pleas were met with further injuries rather than solutions. Events such as British aggression at Lexington and Concord, and Parliament's decisions to control colonial trade and dismiss the American petitions, convinced the colonists that independence was the only remaining path to protect their liberties.