mr. macdonald's surrender re-established the principle that "policy" in this matter was "set" and immutable, and during the ensuing twenty years this became the paramount principle of all british and american state policy.

Please write the text above using proper case.
Mr. Macdonald's surrender re-established the principle that "policy" in this matter was "set" and immutable, and during the ensuing twenty years this became the paramount principle of all British and American state policy.