Why did the American colonists go from being proud, loyal citizens of the greatest empire in the world to rebels who wanted independence from that...

The basic
reason why this happened is that the Americans were "outgrowing" their role as a
colony just as Great Britain was trying to exert more control over them.  This is analagous to a
family in which a child has been given a great deal of freedom, only to have it taken away when
he or she becomes a teenager.  This is a recipe for rebellion.

Before the
French and Indian War, the colonies were given a considerable amount of...