7. How did the Navajo code-talkers aid marines in battle? They could relay a message in minutes that would have taken a code-machine operator hours to encipher and transmit. America andB. Main Idea: The Battle of Midway was the turning point in the war in the Pacific.1. When did the Battle of Midway occur?June 4, 1942 2. How did the Battle of Midway change the course of the war? The Japanese navy lost the heart of its fleet, four large carriers. Six months after Pearl Harbor, the U.S. had stopped the Japanese advance. C. Main Idea: Admiral Nimitz and General MacArthur drove the Japanese back from islandscaptured in the Pacific.1. Why did the U.S. forces launch an island-hopping campaign? Advance through the central Pacific by “hopping” from one island to the next, closer and closer to Japan. 2. How did the amphtrac save lives? The vehicle was a boat with tank tracks and had been able to cross the reef and deliver its troop onto the beaches. 3. What was the Battle of Leyte Gulf? United States assembled an enormous invasion force, over 700 ships carrying more than 160,000 troops sailed for Leyte Gulf in the Philippines. the Japanese sent four aircraft carriers toward the Philippines from the north and secretly dispatched another fleet from the west.How was the United States able to win the war in the Pacific?By breaking the Japanese navy’s secret code for conducting operations. And assembling a large invasion force for the Battle of Leyte Gulf.