Final answer:
The Battle of Coral Sea, fought in May 1942, was crucial in securing Australia from Japanese forces by preventing the further threat of an invasion.
Step-by-step explanation:
The battle that secured Australia from the Japanese forces during World War II was the Battle of Coral Sea. In May of 1942, this crucial battle involved direct confrontations between the naval aviation forces of the United States and Japan. While both sides suffered damages, it was significant for halting a Japanese invasion force that was targeting Australia, thereby preventing the Japanese from further threatening Australian shores. This engagement, along with the Battle of Midway in June 1942, marked the turning point against Japanese expansion in the Pacific. Despite no surface ships exchanging shots at Coral Sea, the battle was fought by carrier-launched planes and was key in stopping the advancement of Japanese forces towards Australia.