Final answer:
Henry David Thoreau's writings, including "On the Duty of Civil Disobedience" and "Walden; or, Life in the Woods," emphasize the cultural value of individualism in American society.
Step-by-step explanation:
The American cultural value that Thoreau highlights in his writings is individualism. Thoreau's works show a strong focus on the idea of the individual striving for freedom from government interference and societal expectations. In works such as "On the Duty of Civil Disobedience" and "Walden; or, Life in the Woods," Thoreau presents a clear argument for the importance of personal freedom and individual rights. These works align with transcendentalist thinking, notably concerned with the autonomy of the individual. The cultural value of individualism, therefore, is a key element in Thoreau's essays and is a concept deeply inherent in American philosophy and lifestyle.