In Washington's farewell address, he corrected people's assumptions that he would serve another term; instead, he decided to retire. Additionally, he warned about the dangers of having close relationships and strong alliances with other countries. He also discouraged the formation of political parties.
It was important, because he was ending his presidency, and he gave a last bit of wisdom for presidents that would follow him.
Answer: The attempts by Britain to tax its North American colonists in the late 1700s led to arguments, war, the expulsion of British rule and the creation of a new nation.