Polk came into the presidency with a focused political agenda and a clear set of convictions. He left office the most successful President since George Washington in the accomplishment of his goals.[285]
Harry S. Truman called Polk "a great president. Said what he intended to do and did it."[286] Bergeron noted that the matters that Polk settled, he settled for his time. The questions of the banking system, and of the tariff, which Polk had made two of the main issues of his presidency, were not significantly revised until the 1860s. Similarly, the Gadsden Purchase, and that of Alaska (1867), were the only major U.S. expansions until the 1890s.[287]
Paul H. Bergeron wrote in his study of Polk's presidency: "Virtually everyone remembers Polk and his expansionist successes. He produced a new map of the United States, which fulfilled a continent-wide vision."[287] "To look at that map," Robert W. Merry concluded, "and to take in the western and southwestern expanse included in it, is to see the magnitude of Polk's presidential accomplishments.