The operation was launched with incredible speed, "a matter of weeks." Perhaps it would not be uncharitable to conclude that the Americans had some unfinished business connected with the war in the polar region. Indeed this was later confirmed by other events and the operation’s leader, Admiral Richard Byrd, himself. However, the official instructions issued by the then Chief of Naval Operations, Chester W. Nimitz, himself of German descent, were to (a) train personnel and test material in the frigid zones; (b) consolidate and extend American sovereignty over the largest practical area of the Antarctic continent; (c) to determine the feasibility of establishing and maintaining bases in the Antarctic and to investigate possible base sites; (d) to develop techniques for establishing and maintaining air bases on the ice, (with particular attention to the later applicability of such techniques to Greenland) amplify existing knowledge of hydrographic, geographic, geological, meteorological and electromagnetic conditions in the area.

More about Operation Highjump (1)

Little other information was released to the media about the mission, although most journalists were suspicious of its true purpose given the huge amount of military hardware involved. The US Navy also strongly emphasized that Operation Highjump was going to be a navy show. Admiral Ramsey’s preliminary orders of 26th August 1946 stated that "The Chief of Naval Operations only will deal with other governmental agencies” and that "No diplomatic negotiations are required. No foreign observers will be accepted."