It is fitting that J. Reuben Clark, Jr.'s, career as a public servant should end with his appointment as Ambassador to Mexico. Traditionally ambassadors have occupied a preeminent position in the world of diplomacy. As the personal representatives of the sovereign, they are protected by a substantial body of international law, and affronts to the ambassador have been treated as affronts to the sovereign himself. In American diplomatic practice, the ambassador is the personal representative of the president. He serves at the pleasure of the president, although his appointment must be confirmed by the Senate. Since the ambassador is presumed to be the personal choice of the president, the reputation and status of the ambassador is frequently regarded by the host country as an indication of the importance which the president places on the United States' relationships with the host country.
J. Reuben Clark's appointment to Mexico, judged by that criterion, was a clear signal to the Mexican government that the United States placed considerable value on amicable Mexican-American relations. Excelsior, a Mexican newspaper with an English language section, headlined the story, reporting Clark's appointment as being the appointment of probably the best man to advance goodwill, understanding, and friendly relations between the United States and Mexico. The Mexican ambassador to the United States welcomed Clark's assignment as a "very happy appointment." A full study of J. Reuben Clark's career as Ambassador to Mexico must await the definitive study of his life, which is now under preparation by David Yarn, but there are two documents which give some insight into Clark's tenure as ambassador, and which can stand alone, apart from a larger context.