After four years of intense fighting in the Pacific, American forces decided they would need airfields nearby to Japan in order to invade the country and hasten an end to the conflict. To achieve this, U.S. commanders turned their focus toward Okinawa and Iwo Jima. Over 70,000 Marines were deployed to Iwo Jima to defeat the Japanese stronghold on Mt. Suribachi and secure the island’s airfields. But the Japanese defenses proved formidable—around 25,000 Japanese troops laid in waiting in well-hidden bunkers and sturdy fortifications. Thirty-six days of combat ensued, resulting in one of the bloodiest battles in history.