Although the US and Filipino forces achieved success in defending Bataan through the end of February, they had taken 50 percent casualties and were worn out and poorly supplied. Also, the British fortress of Singapore had surrendered on 15 February, and the Japanese had taken several major islands of the Dutch East Indies, essentially preventing any reinforcement of the Philippines. Philippine President Manuel Quezon, with his family and senior officials, was evacuated to the southern Philippines by the submarine on 20 February. MacArthur was ordered by President Franklin D. Roosevelt to relocate to Australia to prevent his capture and to direct further operations. He departed Corregidor on 12 March 1942, initially by PT boat to Mindanao, completing his journey by air. On 20 March he made a speech with the famous phrase "I shall return". He left Lieutenant General Jonathan M. Wainwright IV in a subordinate command in the Philippines, telling the key officers there that he (MacArthur) would control the military forces in the Philippines from Australia. However, he neglected to inform Washington of this arrangement, and Washington intended Wainwright to be in charge. It was not until 20 March that the extent of Wainwright's authority and degree of independence from MacArthur was clarified by a message from General George C. Marshall, the Army chief of staff.