The statement that best explains Wright's assertion that he and his father "were forever strangers" is:
Wright is stating that he is emotionally disconnected from his father.
Whenever two persons are strangers to each other. They are ignorant of the other person's thoughts and emotions. When Wright says that he and his father were forever strangers. Wright is highlighting that he was unaware and ignorant to who his father was. Also, one can conclude that his father probably felt the same way.
The British imposed taxes on the colonists because they believed they could not do anything about it. The colonists did not like these taxes (obviously) and later protested the increased taxes with events such as the Boston tea party.