Historian Peter Dean acknowledges the general interpretation that the actions of MacArthur and Blamey were "to salvage their own positions at the expense of the troops" but reports that MacArthur, himself, was under pressure, citing a cable from the US Joint Chiefs to MacArthur of 16 October, "reminding him that they viewed the situation in Papua as 'critical. Dean also notes that this coincided with the relief of Vice Admiral Robert Ghormley, Commander-in-Chief of US forces in the south Pacific who had operational control of the forces engaged at Guadalcanal. The pressure brought to bear by MacArthur was in the face of "complicated operational and strategic contexts", stating that, "an understanding of these contexts has been poorly done in most accounts of the fighting Papua." This is encapsulated in correspondence from Brigadier General Stephen J. Chamberlin (MacArthur's operations chief) to MacArthur's Chief-of-Staff, Richard K. Sutherland, of 30 October 1942: "the key to our plan of action lies in the success or failure of the South Pacific in holding Guadalcanal ..." (that is, that the position at Guadalcanal was tenuous).