On 18 March 1942, he was promoted to the acting rank of vice admiral and given the honorary ranks of lieutenant general and air marshal to have the authority to carry out his duties in Combined Operations; and, despite the misgivings of General Sir Alan Brooke, the Chief of the Imperial General Staff, Mountbatten was placed in the Chiefs of Staff Committee. He was in large part responsible for the planning and organisation of the St Nazaire Raid on 28 March, which put out of action one of the most heavily defended docks in Nazi-occupied France until well after the war's end, the ramifications of which contributed to allied supremacy in the Battle of the Atlantic. After these two successes came the Dieppe Raid of 19 August 1942. He was central in the planning and promotion of the raid on the port of Dieppe. The raid was a marked failure, with casualties of almost 60%, the great majority of them Canadians. Following the Dieppe Raid, Mountbatten became a controversial figure in Canada, with the Royal Canadian Legion distancing itself from him during his visits there during his later career. His relations with Canadian veterans, who blamed him for the losses, "remained frosty" after the war.