"Goering's great air offensive against Great Britain, Operation Eagle (Adlerangriff), had been launched on August 15 with the objective of driving the British Air Force from the skies and thus achieving the one condition on which the launching of the invasion depended. The fat Reich Marshal, as he now was, had no doubts about victory. By mid-July he was confident that British fighter defenses in southern England could be smashed within four days by an all-out assault, thus opening the way for the invasion. To destroy the R.A.F. completely would take a little longer, Goering told the Army High Command: from two to four weeks. In fact, the bemedaled German Air Force chief thought that the Luftwaffe alone could bring Britain to her knees and that an invasion by land forces probably would not be necessary."