In spite of the disaster at Dieppe, the position of the Allies was improving. On the Eastern Front, the Soviets had halted the Nazi juggernaut. The immense military-industrial might of the United States was also mobilizing. The American navy stymied the Japanese fleet at the island of Midway in June 1942. The Japanese invaded Midway in order to engage, and destroy, the smaller US Pacific Fleet. Superior American tactics and intelligence thwarted this ambition. The battle was a crucial turning point in the Pacific campaign as it shifted the balance of sea power to the Allies.
In the Atlantic, the winter of 1942-1943 was particularly bad for Allied shipping. In November 1942, U-boats sank 119 ships. In February 1943, they sank 63. In March of that year, they destroyed 108. But the tide was slowly turning. First, the Allied command granted the RCN (which gained control over its own sector) and the RN authority over convoy operations. More importantly, the Allies launched more and better corvettes and destroyer escorts throughout 1943. They also introduced long-range B-24 Liberator bombers that provided air support for convoys in the "Black Pit," the 300-mile mid-Atlantic gap. Lastly, they put small escort carriers into service that gave vital additional air support to convoys under assault, and Portugal opened airfields in the Azores to Allied patrol aircraft. These developments gave convoys extensive protection throughout the voyage. While the German navy made advances of its own and continued to sink convoy shipping until the end of the war, the Allied navies gradually reduced the U-boat menace.
In North Africa, the British had begun to challenge German control of the desert. Although Rommel and the Afrika Korps had driven deep into Egypt, the British under General Bernard Montgomery halted the German advance. In late October and early November 1942 at El Alamein, Montgomery and the British launched a powerful counterattack that forced the Germans westward. For the next 10 weeks, the British pursued Rommel and his troops across the desert. This British offensive was undertaken in conjunction with a second Allied operation. In November 1942, General Dwight Eisenhower led an amphibious landing in French North Africa. One remarkable feature of this operation is that it was effectively launched directly from the United States. The invading force was mustered on the eastern seaboard, loaded onto ships, and then launched amphibious landings from those ships onto the shores of North Africa. Once established on the ground, Eisenhower's troops began to move to the east, trapping the Afrika Korps between two advancing armies. By the end of May 1943, the Allies would be in control of North Africa.