As secretary [of the navy] Bancroft acquired first-hand experience at conducting foreign policy in a democratic society. He also helped found the U.S. Naval Academy at Annapolis and tried to streamline the Navy Department. Bancroft was instrumental in the acquisition of California, ordering the Pacific Naval Squadron in June 1845 to occupy San Francisco and other ports in case of war, and he defended President Polk against the charge that the president was party to a nefarious southern plot to extend slavery. Bancroft believed that the Mexican War, of which he was an enthusiastic supporter, was a god-sent opportunity to enlarge the national domain for liberty. The vociferous antiwar sentiment, the shifting political alliances the war created, and the strange bedfellows it produced astounded Bancroft.
Lilian Handlin, "Bancroft, George," American National Biography Online, February 2000, http://www.anb.org/articles/14/14-00034.html.