In July 1944, President Roosevelt summoned MacArthur to meet with him in Hawaii "to determine the phase of action against Japan". Nimitz made the case for attacking Formosa. MacArthur stressed America's moral obligation to liberate the Philippines and won Roosevelt's support. In September, Admiral William Halsey Jr.'s carriers made a series of air strikes on the Philippines. Opposition was feeble and Halsey concluded, incorrectly, that Leyte was "wide open" and possibly undefended, and recommended that projected operations be skipped in favor of an assault on Leyte.