The British were deluding themselves, as were the Axis commanders

The Japanese attacks that commenced on 7 December 1941 gave the Axis commanders hope that the United States would be focused on the Pacific War and that British strength would be drained away from the Mediterranean theater. They also had hopes that the Americans would concentrate their efforts in the Pacific, and the Allies would go into a containment strategy against them. The British commanders kept hoping that despite their severe naval losses in the Mediterranean and the tenuous situation in Libya, that they might still mount Operation Acrobat to push the Axis forces out of Tripolitania. They obviously did not anticipate the reversal of the strategic situation that took place in early 1942, where the Germans took control of the air over the Mediterrean and put the British supply situation in jeopardy, in conjunction with increased submarine interdiction of British supply lines and operations against British warships. This is based on the account in Vol.III of the Official History.