Successful Allied initiatives at El Alamein, Stalingrad, French North Africa, and Guadalcanal in November 1942 marked strategic shifts for World War II. Aircraft carriers contributed to the success of these operations by protecting convoys of armaments and other supplies to Egypt and Russia, keeping Malta supplied and able to disrupt Axis supply operations to North Africa, providing air support for troops during the invasion of North Africa, and by helping prevent Japanese troops and supplies from reaching Guadalcanal. Beginning in 1943, the extensive mobilization of American production capability for war resulted in dramatic increases in the number of carriers available for even more strategic initiatives. Overall, aircraft carriers contributed greatly to making 1942 the pivotal,turning point of the war, 1944 the decisive year, and 1945 one for essentially finishing up, albeit at great cost.