and military discipline." Anticipating adverse political reaction to the trial scheduled for November, and desirous of shaping aviation policy to his own economic views, Coolidge asked Morrow to take charge of a board of military, political, and civilian aviation experts to inquire into all aspects of American aviation. The board's report, published before Mitchell's conviction, recommended the creation of an Air Corps within the Army equivalent to the Signal Corps or Quartermaster Corps, which resulted in the establishment of the U.S. Army Air Corps in July 1926. Ambassador to Mexico Morrow was appointed United States Ambassador to Mexico by Coolidge from 1927 to 1930. When Morrow was appointed, the Mexican press had expected that a partner in the financial firm J.P. Morgan was "a return to Dollar Diplomacy." However, the Coolidge administration planned on changed relations between Mexico and the U.S., which Morrow was to implement. One of Morrow's first acts in Mexico was to change the sign identifying the embassy from "American Embassy" to "United States Embassy"; the appropriation of the words "America" and "American" to refer solely to the United States has long rankled other countries in the hemisphere, including Mexico. He was widely hailed as a brilliant ambassador, mixing popular appeal with sound financial advice. In 1927, he invited popular humorist-actor Will Rogers and famed aviator Charles Lindbergh for a goodwill tour of Mexico. His daughter, Anne Morrow, was introduced and soon engaged to Lindbergh. To thank the town of Cuernavaca, where Morrow had a weekend house, Morrow hired the Mexican artist Diego Rivera to paint murals in the Palace of Cortez, which are a chronicle of Mexican history from a post-Mexican Revolution point of view. Morrow initiated a series of breakfast meetings with President Plutarco Elías Calles (1924–1928), at which the two would discuss a range of issues, from the religious uprising, to oil and irrigation. This earned him the nickname "ham and eggs diplomat" in U.S. papers. Morrow also invited Rogers to accompany Morrow and Calles on a tour of Mexico, with Rogers sending favorable human interest stories about Mexico and Mexicans back to U.S. papers, helping to change U.S. perceptions. In a dispute about Mexican petroleum, a continuing issue between the U.S. and Mexico, with U.S. (and other foreign oil interests) pushing for protection of their interests in Mexico, Morrow helped shape the U.S. response to Mexican government actions regarding oil. Morrow's best known