"McVay and the Indianapolis were about to sail from he Marianas Sea Frontier into the Philippine Sea Frontier, and it was like passing between two different worlds. A ship moved from one frontier to the other by crossing the Chop, a boundary marked by the 130-degree line of longitude. Clear as this delineation was, there was a complicating factor: communications in this area were often confused by a political battle between Admiral Nimitz and General MacArthur, who were locked in a struggle to control the Navy. MacArthur, in charge of the Seventh Fleet, wanted to unite it with the Army. Nimitz, commander of the Pacific Fleet, wanted to remain autonomous. In the end, Nimitz had been given control of the entire Pacific naval operation, but friction between the two military titans still existed. Information about a ship's whereabouts, or other crucial facts, sometimes got lost in the fallout. This could mean trouble for the Indianapolis, which sometimes relied on the presence of carefully-timed escorts to protect her from enemy submarines and spirit her out of danger."