frequently cited Mahan's thesis that whatever power was the greatest sea power was also the world's greatest power. Lothian claimed that the United States had benefitted from the Pax Britannica of the 19th century as he maintained that the Royal Navy had protected the United States just as much as the United Kingdom during the "short 19th century" of 1815–1914. Using Mahan's theories as his basis, Lothian claimed that a Germany that dominated the seas would inevitably come into conflict with the United States, and thereby reversed the arguments of American isolationists by claiming the best way to keep the United States out of the war was by aiding Britain. Lothian claimed that as long as Britain dominated the seas, there was no prospect of a German-American war, thereby making aiding Britain the best way of the United States to avoid entering the war. In a speech in Chicago, Lothian stated that the Royal Navy was the United States' "first line of defense", saying that as long the Royal Navy ruled the seas there was no danger of a German invasion of anywhere in the New World. Lothian noted that Germany had emerged as a major economic competitor to the United States in Latin America, and argued that if Britain were defeated, then the Monroe Doctrine would become moot as he envisioned a future where the Kriegsmarine ruled the Atlantic, allowing the Reich to project power anywhere it wanted in Latin America. Lothian's choice of Chicago to deliver this speech was no accident. The American Midwest was a stronghold of isolationism, and Lothian chose Chicago as a way to reach an audience that was particularly opposed to American aid to Britain. Cadogan and the other professional diplomats at the Foreign Office objected to the Chicago speech, saying that speeches like the one he delivered in Chicago would led to charges of British inference in the American presidential election. Lothian in response wrote that his speeches "have been a success here precisely because I have felt that I knew the American mind well enough to be quite frank and to deal frankly with controversial issues. I can imagine what my speeches would have been like if they had been minuted by all the veterans of the Foreign Office at home!" In an article in Time, Lothian's Chicgo speech was described as "one of the most effective, skillful briefs yet delivered for