Over three days of intense fighting, thousands of soldiers died on beaches and in the ocean for a prize — a strategic speck of coral sand and its critical air strip, in the middle of the Pacific — that would help decide the outcome of World War II.

Eighty years ago, the U.S. military attacked the island of Betio, part of the Tarawa atoll in what is today the archipelago nation of Kiribati, to wrest it from Japanese control.

At just 4 kilometers (2.5 miles) in length, Betio had little significance. But its location would allow the United States to move northwest: first to the Marshall Islands, then to the Mariana Islands and eventually to Japan itself. These were the "leapfrogging” tactics the Allies used in the Pacific to weaken Japan’s control of the region as well as to establish bases to launch further attacks.