Why was General MacArthur sent to the Philippines?

Answer 1

He was not sent. He "retired" in 1937, after thirty-six years of service. From 1931 to October 1935 he was Chief of Staff of the US Army, which is the top general in the army. This is a little longer than a general usually holds this position. After holding this position he reverted to his permanent rank of Major General (two stars). But his position was unusual and anomalous, as former commander of the Army, it was difficult for him to continue to serve and difficult for the new Chief of Staff with a former army commander still on the active list. He then accepted a job as Field Marshal of the Philippine Army. He remained on the active list but took this job with the permission of President Roosevelt. He was out of the country and out of the army's chain of command. The Philippines were at that time a US possession, and American troops were also based in the Philippines, but not as many as MacArthur's native force. The Philippines had achieved semi-independent status in 1935. When war clouds began to gather MacArthur was "recalled" to active duty in July 1941 as a Major General.

MacArthur was not in the continental US from the time he went to the Philippines until fired by Truman in 1951, except for a WWII visit to Hawaii to consult with Roosevelt. Hawaii was still a territory at the time, and not yet a state.