Hughes's major foreign policy achievement was the Washington Naval Conference of 1921–1922, in which the world's major naval powers agreed on a naval disarmament program. Harding appointed four Supreme Court justices, all of whom became conservative members of the Taft Court. Shortly after Harding's death, several major scandals emerged, including the Teapot Dome scandal. In historical rankings of the U.S. presidents, Harding is often rated among the worst. By the time the 1920 Republican National Convention began in June, a Senate sub-committee had tallied the monies spent by the various candidates, with totals as follows: Wood – $1.8 million; Lowden – $414,000; Johnson – $194,000; and Harding – $114,000; the committed delegate count at the opening gavel was: Wood – 124; Johnson – 112; Lowden – 72; Harding – 39. Delegates then selected Massachusetts governor Calvin Coolidge to be his vice-presidential running mate. Arriving via Vancouver Harbor on July 26, Harding became the first sitting U.S. president to visit Canada.