“An attention to the judgment of other nations is important to every government for two reasons: the one is that, independently of the merits of any particular plan or measure, it is desirable on various accounts that it should appear to other nations as the offspring of a wise and honorable policy: the second is that, in doubtful cases, particularly where the national councils may be warped by some strong passion or momentary interest, the presumed or known opinion of the impartial world may be the best guide that can be followed.”

From Federalist 63 (but including modernization of comma rules)